Sustainable beeswax modified cellulose paper for the determination of tricyclic antidepressants in biofluids

This article describes the synthesis of sorptive phases for bioanalysis based on the modification of cellulose paper with natural beeswax as sorbent, resulting in a substrate completely renewable and sustainable. The preparation of the sorptive phases consisted of the dissolution of beeswax in hexane, followed by its drop-casting on cellulose paper and subsequent evaporation of the solvent. The beeswax modification of paper renders it hydrophobic, enabling the extraction of the target analytes, i.e., imipramine, desipramine, amitriptyline and trimipramine, via hydrophobic interactions. The main variables affecting the extraction performance were investigated (e.g., pH, ionic strength, extraction time, eluent composition, agitation speed). The analytical workflow combines a straightforward sampling, simultaneous extraction of 30 samples in 1 h, and the rapid (<2 min) determination of the analytes via direct infusion mass spectrometry. The method provided limits of detection in the range 2.0 and 3.2 μg L-1, and the precision, expressed as relative standard deviation, was better than 5.4 % and 8.5 % for intra and inter-day analyses, respectively. The accuracy, in terms of relative recovery, ranged from 90 % to 121 % using saliva as model biofluid.

Association between depression, antidepressant use, and the incidence of atherosclerotic cardiovascular diseases

OBJECTIVE

To examine the association between depression, the use of antidepressants, and atherosclerotic cardiovascular disease (ASCVD).

METHODS

The South Korean national claims data was used. Among a nationally representative population, 273,656 subjects who had been diagnosed with depression and prescribed antidepressants ("DEP with antidepressants") and 78,851 subjects who had been diagnosed with depression but not prescribed antidepressants ("DEP without antidepressants") were identified to be eligible. Healthy controls (HCs) were 1:1 matched with DEP with antidepressants group for age and sex. We followed up on the occurrence of ASCVD including ischemic heart diseases and ischemic stroke.

RESULTS

The risk of ASCVD was increased in the DEP with antidepressants group and decreased in the DEP without antidepressants group compared to HCs. Among those under antidepressants, tricyclic antidepressant users showed the highest risk of ASCVD compared to HCs. Among young adults, the risk of ASCVD was increased in both groups.

CONCLUSION

The risk of ASCVD increased in depression patients taking antidepressants, while it decreased in depression patients not taking antidepressants. However, the relationship showed differences according to drug class and age group.

Acupuncture versus tricyclic antidepressants in the prophylactic treatment of tension-type headaches: an indirect treatment comparison meta-analysis

BACKGROUND

Acupuncture showed better improvement than sham acupuncture in reducing attack frequency of tension-type headache (TTH), but its effectiveness relative to first-line drugs for TTH is unknown, which impedes the recommendation of acupuncture for patients who are intolerant to drugs for TTH. We aimed to estimate the relative effectiveness between acupuncture and tricyclic antidepressants (TCAs) through indirect treatment comparison (ITC) meta-analysis.

METHODS

We searched Ovid Medline, Embase, and Cochrane Library from database inception until April 13, 2023. Randomized controlled trials of TCAs or acupuncture in the prevention of TTH in adults were included. The primary outcome was headache frequency. The secondary outcomes were headache intensity, responder rate, and adverse event rate. Bayesian random-effect models were used to perform ITC meta-analysis, and confidence of evidence was evaluated by using the GRADE approach.

RESULTS

A total of 34 trials involving 4426 participants were included. Acupuncture had similar effect with TCAs in decreasing TTH frequency (amitriptyline: mean difference [MD] -1.29, 95% CI -5.28 to 3.02; amitriptylinoxide: MD -0.05, 95% CI -6.86 to 7.06) and reducing TTH intensity (amitriptyline: MD 2.35, 95% CI -1.20 to 5.78; clomipramine: MD 1.83, 95% CI -4.23 to 8.20). Amitriptyline had a higher rate of adverse events than acupuncture (OR 4.73, 95% CI 1.42 to 14.23).

CONCLUSION

Acupuncture had similar effect as TCAs in reducing headache frequency of TTH, and acupuncture had a lower adverse events rate than amitriptyline, as shown by very low certainty of evidence.

Antidepressant use and ovarian cancer risk: Evidence from nationwide studies with >14,000 cases from Denmark and Sweden

OBJECTIVE

Given that the evidence regarding the link between antidepressant use and ovarian cancer risk is equivocal, we investigated this research question by conducting two nationwide nested case-control studies among the Danish and Swedish populations.

METHODS

Altogether, 14,121 women with epithelial ovarian cancer (30-84 years old) (Denmark: 8976 diagnosed 2000-2019, Sweden: 5145 diagnosed 2010-2018) were randomly age-matched with 564,840 female controls (359,040 from Denmark, and 205,800 from Sweden) using risk set sampling. We used conditional logistic regression to estimate odds ratios (OR) with 95 % confidence intervals (CI) and combined the estimates based on the fixed-effect assumption. We also investigated potential effect modification by well-established risk factors for ovarian cancer.

RESULTS

Antidepressant use was associated with an overall reduced risk of ovarian cancer (OR = 0.92, 95%CI: 0.88-0.96), and that reduction was more pronounced in postmenopausal women and long-term users. The effect was most pronounced for serous ovarian tumors (OR = 0.90, 95%CI: 0.86-0.95) but was also observed in other subtypes, although not statistically significant. Among different types of antidepressants, selective serotonin reuptake inhibitors in general and citalopram in particular exhibited a noteworthy reduction in ovarian cancer risk (OR = 0.89, 95%CI: 0.82-0.96). Additionally, use of oral contraceptives and hormone replacement therapy individually modified the association between antidepressant use and ovarian cancer risk.

CONCLUSIONS

Use of an antidepressant was associated with a slight, but statistically significant, decrease in ovarian cancer risk. Given the morbidity and mortality associated with ovarian cancer, and increasing use of antidepressants, these findings may be of significance to cancer prevention and should be studied in more detail mechanistically.

Applying children's enuresis treatment with amitriptyline for canine post-spaying urinary incontinence: A pilot estriol-controlled randomized clinical trial

Urinary incontinence due to urethral sphincter mechanism incompetence (USMI) affects up to 20% of bitches that undergo spaying surgery. Amitriptyline is a tricyclic antidepressant whose urinary retention is a reported side effect. This study aimed to assess the efficacy and safety of amitriptyline when compared to estriol orally. Fifteen bitches with a clinical diagnosis of post-spaying UI were evaluated during 60 days in a non-blinded randomized clinical trial. All patients were enrolled after clinical evaluation consisting of anamnesis, physical examination, and complementary exams (complete blood count, biochemical parameters, urinalysis, and abdominal ultrasound). The amitriptyline (AMT) group consisted of 8 bitches, which received the initial dose of 1 mg/kg every 12 h, whereas the estriol (EST) group consisted of 7 bitches which were initially treated with 1 mg/animal every 24 h. Patients underwent clinical evaluation at 7 days, and then at 21 and 60 days of treatment to assess safety and efficacy, as well as adjustments of dose when necessary. A urinary incontinence scale was used to assess the level of incontinence and therapeutic response to treatment. During the period of the study, estriol was fully effective in 71% of cases and amitriptyline in 62%. Both drugs proved safe in the medical treatment of USMI, with adverse effects such as somnolence (AMT, n = 5/8) and male attraction (EST, n = 1/7). The results support the amitriptyline recommendation as a substitute for estriol in USMI treatment.

Growth of bimetallic Ni-Co MOFs on a skeleton of electrospun PAN nanofibers and coating on a thin film for SPME of amitriptyline and nortriptyline in urine and plasma samples

In this research, composited bimetallic organic framework-polyacrylonitrile (Ni-Co MOFs-PAN) was applied for thin-film solid phase microextraction (TF-SPME) of tricyclic antidepressant (TCA) drugs from biological samples. The separation and quantification of the analytes were accomplished by HPLC-UV. First, seeded nanofibers with organic ligands were electrospun on a sheet of foil. Then, with the uniform in-situ solvothermal growth of Ni-Co MOFs on the skeletal surface of nanofibers, the nanoparticles were successfully attached to the surfaces without effective bonds and produced a thin layer with a high flexibility, large active surface and abundant functional groups for adsorption. The characteristics of the produced nanocomposite were investigated by Fourier-transform infrared spectroscopy, field emission-scanning electron microscopy, X-ray diffraction, energy dispersive X-ray spectroscopy and Brunauer-Emmett-Teller analysis. The stirring rate, pH, ionic strength, adsorption and desorption time along with type and volume of desorption solvents as influential factors on extraction efficiencies of the analytes, were optimized by one variable at a time method. Under optimized conditions, wide linear range for analytes in water and plasma matrices were obtained from 0.2 to 1000.0 μg L-1 and 1.0-1000.0 μg L-1, respectively, with R2 ≥ 0.9925. The limits of detection were in the range of 0.06-0.3 μg L-1 in different media. Good repeatability and reproducibility were attained within intra-day, inter-day and film-to-film RSDs% (n = 3) below 3.3 %, 3.9 % and 4.7 %, respectively. Since desirable relative recoveries were calculated between 91.4 % and 100.4 %. The method can be used for the successful extraction and measurement of amitriptyline and nortriptyline as its metabolite in different sampling time from urine and plasma matrices.

A new view on the mechanism of UV photodegradation of the tricyclic antidepressant carbamazepine in aqueous solutions

Mechanism of direct UV photolysis of the tricyclic antidepressant carbamazepine (CBZ) at neutral pH was revealed by a combination of nanosecond laser flash photolysis, steady-state photolysis combined with high resolution LC-MS and DFT quantum-chemical calculations. The detection of short-lived intermediates and the detailed identification of final products were performed for the first time. The quantum yield of CBZ photodegradation (282 nm) is about 0.1% and 0.18% in air-equilibrated and argon-saturated solutions. The primary stage is photoionization with the formation of CBZ cation radical followed by a rapid nucleophilic attack by a solvent molecule. The primary photoproducts are 10-oxo-9-hydro-carbamazepine, 9-formylacridine-10(9H)-carboxamide (a result of ring contraction) and various isomers of hydroxylated CBZ. Prolonged irradiation results to accumulation of acridine derivatives, which should lead to an increase of the toxicity of photolyzed CBZ solutions. The obtained results may be important for understanding the fate of tricyclic antidepressants in processes of UVC disinfection and in natural waters under action of sunlight.

The harmful acute effects of clomipramine in the rat liver: impairments in mitochondrial bioenergetics

Clomipramine, a tricyclic antidepressant used to treat depression and obsessive-compulsive disorder, has been linked to a few cases of acute hepatotoxicity. It is also recognized as a compound that hinders the functioning of mitochondria. Hence, the effects of clomipramine on mitochondria should endanger processes that are somewhat connected to energy metabolism in the liver. For this reason, the primary aim of this study was to examine how the effects of clomipramine on mitochondrial functions manifest in the intact liver. For this purpose, we used the isolated perfused rat liver, but also isolated hepatocytes and isolated mitochondria as experimental systems. According to the findings, clomipramine harmed metabolic processes and the cellular structure of the liver, especially the membrane structure. The considerable decrease in oxygen consumption in perfused livers strongly suggested that the mechanism of clomipramine toxicity involves the disruption of mitochondrial functions. Coherently, it could be observed that clomipramine inhibited both gluconeogenesis and ureagenesis, two processes that rely on ATP production within the mitochondria. Half-maximal inhibitory concentrations for gluconeogenesis and ureagenesis ranged from 36.87μM to 59.64μM. The levels of ATP as well as the ATP/ADP and ATP/AMP ratios were reduced, but distinctly, between the livers of fasted and fed rats. The results obtained from experiments conducted on isolated hepatocytes and isolated mitochondria unambiguously confirmed previous propositions about the effects of clomipramine on mitochondrial functions. These findings revealed at least three distinct mechanisms of action, including uncoupling of oxidative phosphorylation, inhibition of the F_oF₁-ATP synthase complex, and inhibition of mitochondrial electron flow. The elevation in activity of cytosolic and mitochondrial enzymes detected in the effluent perfusate from perfused livers, coupled with the increase in aminotransferase release and trypan blue uptake observed in isolated hepatocytes, provided further evidence of the hepatotoxicity of clomipramine. It can be concluded that impaired mitochondrial bioenergetics and cellular damage are important factors underlying the hepatotoxicity of clomipramine and that taking excessive amounts of clomipramine can lead to several risks including decreased ATP production, severe hypoglycemia, and potentially fatal outcomes.

Low concentrations of tricyclic antidepressants stimulate TRPC4 channel activity by acting as an opioid receptor ligand

Traditionally prescribed for mood disorders, tricyclic antidepressants (TCAs) have shown promising therapeutic effects on chronic neuralgia and irritable bowel syndrome. However, the mechanism by which these atypical effects manifest is unclear. Among the proposed mechanisms is the well-known pain-related inhibitory G-protein coupled receptor (G_iPCR), namely, the opioid receptor (OR). Here, we confirmed that TCA indeed stimulates OR and regulates the gating of TRPC4, a downstream signaling of the G_i-pathway. In an ELISA to quantify the amount of intracellular cAMP, a downstream product of OR/G_i-pathway, treatment with amitriptyline (AMI) showed a decrease in [cAMP]_i similar to that of the μOR agonist. Next, we explored the binding site of TCA by modeling the previously revealed ligand-bound structure of μOR. A conserved aspartate residue of ORs was predicted to participate in salt bridge interaction with the amine group of TCAs, and in aspartate-to-arginine mutation, AMI did not decrease the FRET-based binding efficiency between the ORs and Gα_i2. As an alternative way to monitor the downstream signaling of G_i-pathway, we evaluated the functional activity of TRPC4 channel, as it is well known to be activated by Gα_i. TCAs increased the TRPC4 current through ORs, and TCA-evoked TRPC4 activation was abolished by an inhibitor of Gα_i2 or its dominant-negative mutant. As expected, TCA-evoked activation of TRPC4 was not observed in the aspartate mutants of OR. Taken together, OR could be proclaimed as a promising target among numerous binding partners of TCA, and TCA-evoked TRPC4 activation may help to explain the nonopioid analgesic effect of TCA.

Frequency of antidepressant use and clinical characteristics of children and adolescents undergoing polysomnography: an observational study

BACKGROUND

Antidepressants are increasingly used in children for various psychiatric disorders but also for sleep disorders such as insomnia; however, it is currently unknown how many children undergoing polysomnography (PSG) are taking anti-depressants. The aims were: to determine the frequency of use of antidepressants in paediatric patients referred for PSG, to identify the most common antidepressants used, to investigate the reasons for their use, and to analyse the PSG parameters found in children taking antidepressants.

METHOD

An observational cross-sectional retrospective chart review of all children undergoing PSG at Seattle Children's Hospital from 6/14/2020 to 12/8/2022 was carried out. Clinical features (such as diagnosis, especially psychiatric), sleep disorders (such as insomnia and restless sleep), and class of antidepressant used [selective serotonin reuptake inhibitors (SSRIs), serotonin and norepinephrine reuptake inhibitors (SNRIs), tricyclic antidepressants (TCA), or atypical antidepressants], and PSG parameters were collected for further analysis.

RESULTS

Among 3,371 patients who underwent PSG during the study, 367 children were selected who were taking one antidepressant only (154 boys and 213 girls, mean age was 13.7 ± years 3.69). A significantly decreased sleep stage N3 was found in girls, who were older than boys. Children with insomnia had longer sleep latency than children without, but more N3. There was a prolonged rapid eye movement (REM) sleep latency in children with attention-deficit/hyperactivity disorder and children with autism. REM latency was longer and REM percentage smaller in children taking SNRIs. Periodic leg movement index ≥ 5/hour was found in a higher number of children taking SSRIs or SNRIs (24.9%) than in subjects taking TCA or atypical antidepressants (13.3%) (chi-square 5.29, p = 0.013).

CONCLUSIONS

Child and adolescent psychiatrists should question about the effects on sleep (both positive and negative) after initiating therapy with antidepressant medications.

Risk of cardiovascular events according to the tricyclic antidepressant dosage in patients with chronic pain: a retrospective cohort study

PURPOSE

We aimed to examine the risk of cardiovascular adverse events by tricyclic antidepressant (TCA) dosage among patients with chronic pain.

METHODS

A retrospective cohort study was conducted using a nationwide sample cohort. Among patients aged ≥ 18 years with a chronic pain diagnosis and no history of cardiovascular events, we extracted users and non-users of TCAs through 1:1 propensity score matching. TCA users were categorized into three groups according to the mean defined daily dose (DDD): very low doses (< 0.15 DDD), low doses (0.15-0.34 DDD), and traditional doses (≥ 0.34 DDD). A 6-month follow-up was conducted with an intention-to-treat approach. We examined the hazard ratio of cardiovascular adverse events using Cox proportional hazards analysis.

RESULTS

In total, 16,660 matched patients were followed up (8330 TCA users and 8330 non-users). TCA use did not significantly increase cardiovascular adverse events (hazard ratio [HR] 1.12, 95% confidence interval [CI] 0.94-1.33). Low-dose (0.15-0.34 DDD) TCAs (HR 1.37, 95% CI 1.08-1.74), particularly low-dose (0.15-0.34 DDD) nortriptyline (HR 2.11, 95% CI 1.44-3.08), was associated with an increased risk of cardiovascular adverse events. Administration of TCAs at the traditional dose (≥ 0.34 DDD) increased the risk of ischemic stroke (HR 2.08, 95% CI 1.11-3.88).

CONCLUSION

Close monitoring of patients on long-term, low-dose use of TCAs should be conducted to avoid an increase in the cumulative dose, which increases the risk of cardiovascular adverse events.

The effect of initial antidepressant type on treatment adherence in outpatients with new onset depression

BACKGROUND

Continuous use of antidepressants can relieve depressive symptoms and prevent recurrence in people with depression; however, many studies have reported low drug compliance rates. This study aimed to investigate the relationship between the type of initial antidepressants and treatment adherence in outpatients with new onset depression.

METHODS

This was a retrospective cohort study using National Health Insurance claim data for services provided in 2012. We examined data from 142,336 individuals aged 18 years or older, who were continuously enrolled in treatment after a new episode of depression, and had initiated antidepressant treatment. A new diagnosis of depression, is defined as a first reported diagnosis of depression in the preceding five years. Adherence was operationally defined as the antidepressant being dispensed to the patient at least 80% of the time during the first three- and six-month treatment periods. To investigate the relationship between the initial type of antidepressants and treatment adherence, we estimated adjusted odds ratios and 95% confidence intervals using logistic regression analysis, adjusting for socio-demographic and health care utilization characteristics.

RESULTS

A statistically significant association was found between initial antidepressant type and adherence in the first three- and six-month treatment periods for employed and self-employed patients newly diagnosed with major depression. In addition, patients with starting prescriptions for tricyclic antidepressants had significantly lower adherence compared to selective serotonin reuptake inhibitors.

LIMITATIONS

This study used national insurance data; therefore, only variables on the claim form were available, and psychological and environmental factors were not considered.

CONCLUSIONS

This was the first study to demonstrate the relationship between initial antidepressant type and treatment adherence among Korean outpatients with new onset depression.

Dose effects of tricyclic antidepressants in the treatment of acute depression - A systematic review and meta-analysis of randomized trials

BACKGROUND

Tricyclic antidepressants (TCA) continue to be an important group of drugs, but it is unclear whether a dose-response relationship is supported by high-level evidence.

METHODS

Systematic review in the Cochrane Collaboration's Central Register of Controlled Trials (CENTRAL) of studies randomizing patients to at least two doses of one TCA, complemented by searches in Medline, Embase, and PsycInfo. In multilevel regression, we calculated the standardized mean difference (SMD) in antidepressant efficacy per mg TCA dose increase, and we analyzed drop-outs due to adverse events. Finally, we computed random effects meta-analyses of all dose comparisons investigated in a minimum of two studies.

RESULTS

Out of 5365 studies screened, we included 15 randomized trials on 24 comparisons of 14 different dose contrasts. We found a statistically non-significant positive effect of increasing the dose: 0.34 SMD with 100 mg/d dose increase ([-0.03; 0.70] p = 0.073). While several comparisons showed no clear signal of a dose gradient, 300 mg of imipramine/desipramine is statistically significantly superior to 150 mg (SMD: 0.80 [0.28; 1.33], p = 0.003, I²: 0%). Drop-outs increased with higher doses, albeit not statistically significantly: Odds ratio (OR) of 1.44 with 100 mg dose increase [0.54; 3.86]. Overall, risk of bias was high.

LIMITATIONS

Limited number of studies with mainly high risk of bias.

CONCLUSIONS

So far, data on a dose-response relationship in TCAs from direct dose comparisons are inconclusive. Clinically, escalation to high doses may be justified if side effects are bearable.

Stir bar sorptive-dispersive microextraction by a poly(methacrylic acid-co-ethylene glycol dimethacrylate)-based magnetic sorbent for the determination of tricyclic antidepressants and their main active metabolites in human urine

A poly(methacrylic acid-co-ethylene glycol dimethacrylate)-based magnetic sorbent was used for the rapid and sensitive determination of tricyclic antidepressants and their main active metabolites in human urine. This material was characterized by magnetism measurements, zeta potential, scanning electron microscopy, nitrogen adsorption-desorption isotherms, and thermogravimetric analysis. The proposed analytical method is based on stir bar sorptive-dispersive microextraction (SBSDME) followed by liquid chromatography-tandem mass spectrometry. The main parameters involved in the extraction step were optimized by using the response surface methodology as a multivariate optimization method, whereas a univariate approach was employed to study the desorption parameters. Under the optimized conditions, the proposed method was properly validated showing good linearity (at least up to 50 ng mL-1) and enrichment factors (13-22), limits of detection and quantification in the low ng L-1 range (1.4-7.0 ng L-1), and good intra- and inter-day repeatability (relative standard deviations below 15%). Matrix effects were observed for the direct analysis of urine samples, but they were negligible when a 1:1 v/v dilution with deionized water was performed. Finally, the method was successfully applied to human urine samples from three volunteers, one of them consuming a prescribed drug for depression that tested positive for clomipramine and its main active metabolite. Quantitative relative recoveries (80-113%) were obtained by external calibration. The present work expands the applicability of the SBSDME to new analytes and new types of magnetic sorbents.

Comparison of the effect of citalopram, bupropion, sertraline, and tricyclic antidepressants on QTc: A cross-sectional study

BACKGROUND

Some data suggests that citalopram has more risk of corrected QT interval (QTc) prolongation than other selective serotonin reuptake inhibitors. Consequently the U.S. Food and Drug Administration distributed a safety warning limiting the maximum dose for citalopram. There is also a suggestion that bupropion may decrease QTc in patients on drugs that increase QTc. The goals of this cross-sectional study were to examine (1) effects on QTc of citalopram compared to sertraline, bupropion, and tricyclic antidepressants; (2) dose dependent effects of citalopram; and (3) effects of bupropion on citalopram-mediated changes in QTc.

METHODS

Records of subjects who received an EKG while taking one of the specified antidepressants were reviewed to collect demographic information, antidepressant history, and information about other confounders. Linear regression was used to examine the relationship between QTc and antidepressants.

RESULTS

487 subjects provided 798 EKG records. The sample was 95% male with an average age of 61 years. No differences were found in QTc between citalopram and other antidepressants. No dose relationship was detected between citalopram and QTc. Bupropion did not affect the relationship between citalopram and QTc (coefficient = -3.4; 95%CI = -14.2, 7.5; p = 0.54).

LIMITATIONS

Observational study designs are prone to biases from retrospective data collection. Some data subsets had small numbers of subjects.

CONCLUSIONS

No effect of citalopram on QTc was found at therapeutic doses. Neither was there evidence of a "QTc-sparing" effect of bupropion. The risk of adverse cardiovascular effects from citalopram at doses of 60 mg per day or less appears minimal.

6-Nitrodopamine is an endogenous mediator of rat isolated epididymal vas deferens contractions induced by electric-field stimulation

6-nitrodopamine (6-ND) is released from human umbilical cord vessels and modulates vascular reactivity by acting as a dopamine antagonist. Here we investigate whether 6-ND is released by the rat isolated vas deferens and its effect on this tissue. Dopamine, noradrenaline, adrenaline and 6-ND levels were quantified in rat isolated vas deferens by LC-MS-MS. Electric-field stimulation (EFS) and concentration-response curves to 6-ND, noradrenaline, dopamine and adrenaline were performed in the absence and in the presence (30 min) of L-NAME, SCH-23390, haloperidol, PG-01037, sonepiprazole, desipramine, clomipramine, amitriptyline, cyclobenzaprine, carbamazepine, maprotiline, paroxetine, oxcarbazepine and ketanserin in the rat isolated epididymal vas deferens (RIEVD). Basal releases of 6-ND and noradrenaline were detected from the rat isolated vas deferens. 6-ND release was reduced by tissue incubation with L-NAME and from the vas deferens obtained from L-NAME-treated rats. SCH-23390 caused leftward shifts on concentration-response curves to 6-ND without affecting dopamine- or EFS-induced RIEVD contractions. Haloperidol, PG-01037 and sonepiprazole caused significant rightward shifts on concentration-response curves to dopamine but had no effect on either the 6-ND or EFS-induced RIEVD contractions. The tricyclic compounds desipramine, clomipramine, amitriptyline, cyclobenzaprine and carbamazepine induced rightward shifts on 6-ND concentration-response curve but did not reduce the noradrenaline, dopamine and adrenaline contractile responses. They also reduced the EFS-induced RIEVD contractions in control but not in tissues obtained from L-NAME-treated animals. Maprotiline, oxcarbazepine, paroxetine and ketanserin had no effect in either 6-ND or EFS-induced RIEVD contractions. Thus, 6-ND modulates RIEVD contractility, and desipramine, clomipramine, amitriptyline, cyclobenzaprine and carbamazepine act as selective 6-ND receptor antagonists.

Tricyclic antidepressants for major depressive disorder: a comprehensive evaluation of current practice in the Netherlands

BACKGROUND

Traditionally tricyclic antidepressants (TCAs) have an important place in treatment of major depressive disorder (MDD). Today, often other antidepressant medications are considered as first step in the pharmacological treatment of MDD, mainly because they are associated with less adverse effects, whereby the position of TCAs appears unclear. In this study we aimed to examine the current practice of TCAs in treatment of unipolar MDD.

METHODS

A mixed methods approach was applied. First, a selection of leading international and national guidelines was reviewed. Second, actual TCA prescription was examined by analyzing health records of 75 MDD patients treated with the TCAs nortriptyline, clomipramine or imipramine in different centers in the Netherlands. Third, promotors and barriers influencing the choice for TCAs and dosing strategies were explored using semi-structured interviews with 24 Dutch psychiatrists.

RESULTS

Clinical practice guidelines were sometimes indirective and inconsistent with each other. Health records revealed that most patients (71%) attained therapeutic plasma concentrations within two months of TCA use. Patients who achieved therapeutic plasma concentrations reached them on average after 19.6 days (SD 10.9). Both health records and interviews indicated that therapeutic nortriptyline concentrations were attained faster compared to other TCAs. Various factors were identified influencing the choice for TCAs and dosing by psychiatrists.

CONCLUSIONS

Guideline recommendations and clinical practice regarding TCA prescription for MDD vary. To increase consistency in clinical practice we recommend development of an up-to-date guideline integrating selection and dosing of TCAs, including the roles of therapeutic drug monitoring and pharmacogenetics. Such a guideline is currently lacking and would contribute to optimal TCA treatment, whereby efficacy and tolerability may be increased.

An electrophysiological model of major depression: Relevance to clinical subtyping and pharmacological management

We present a neurochemical model of unipolar major depressive disorder that makes predictions for optimizing pharmacological treatment of this debilitating neuropsychiatric disorder. We suggest that there are two principal electrophysiological subtypes of depression, with the more common one involving a high excitatory/inhibitory (E/I) electrophysiological ratio, and a less common low E/I subtype. The high E/I subtype is paradoxically a variant of previous conceptions of atypical depression, whereas the low E/I subtype is a variant of melancholic depression. We focus on the ratio of norepinephrine (NE) to serotonin (5HT) as primary determinants of E/I ratio, which have opposing effects on mood regulation. We suggest that high NE/5HT (or E/I) ratio depressions should be treated with pharmacological agents that boost 5HT (such as SSRIs) and/or drugs that reduce noradrenergic transmission (such as clonidine, guanfacine, propranolol, prazosin). In contrast, low NE/5HT (or E/I) depressions should be treated with agents that boost NE (such as most tricyclics) and/or drugs that reduce serotonergic transmission. Our model predicts that the rapidly acting antidepressant ketamine (and possibly scopolamine), which has an acutely excitatory electrophysiological profile that may be followed by sustained increased inhibition, should improve the high NE/5HT subtype and worsen the low subtype.

Tricyclic antidepressants versus 'active placebo', placebo or no intervention for adults with major depressive disorder: a protocol for a systematic review with meta-analysis and Trial Sequential Analysis

BACKGROUND

Major depressive disorder is a common psychiatric disorder causing great burden on patients and societies. Tricyclic antidepressants are frequently used worldwide to treat patients with major depressive disorder. It has repeatedly been shown that tricyclic antidepressants reduce depressive symptoms with a statistically significant effect, but the effect is small and of questionable clinical importance. Moreover, the beneficial and harmful effects of all types of tricyclic antidepressants have not previously been systematically assessed. Therefore, we aim to investigate the beneficial and harmful effects of tricyclic antidepressants versus 'active placebo', placebo or no intervention for adults with major depressive disorder.

METHODS

This is a protocol for a systematic review with meta-analysis that will be reported as recommended by Preferred Reporting Items for Systematic Reviews and Meta-Analysis Protocols, bias will be assessed with the Cochrane Risk of Bias tool-version 2, our eight-step procedure will be used to assess if the thresholds for clinical significance are crossed, Trial Sequential Analysis will be conducted to control random errors and the certainty of the evidence will be assessed with the Grading of Recommendations Assessment, Development and Evaluation approach. To identify relevant trials, we will search both for published and unpublished trials in major medical databases and trial registers, such as CENTRAL, MEDLINE, EMBASE and ClinicalTrials.gov from their inception to 12 May 2021. Clinical study reports will be applied for from regulatory authorities and pharmaceutical companies. Two review authors will independently screen the results from the literature searches, extract data and perform risk of bias assessment. We will include any published or unpublished randomised clinical trial comparing tricyclic antidepressants with 'active placebo', placebo or no intervention for adults with major depressive disorder. The following interventions will be assessed: amineptine, amitriptyline, amoxapine, butriptyline, cianopramine, clomipramine, desipramine, demexiptiline, dibenzepin, dosulepin, dothiepin, doxepin, imipramine, iprindole, lofepramine, maprotiline, melitracen, metapramine, nortriptyline, noxiptiline, opipramol, protriptyline, tianeptine, trimipramine and quinupramine. Primary outcomes will be depressive symptoms, serious adverse events and quality of life. Secondary outcomes will be suicide or suicide-attempts and non-serious adverse events. If feasible, we will assess the intervention effects using random-effects and fixed-effect meta-analyses.

DISCUSSION

Tricyclic antidepressants are recommended by clinical guidelines and frequently used worldwide in the treatment of major depressive disorder. There is a need for a thorough systematic review to provide the necessary background for weighing the benefits against the harms. This review will ultimately inform best practice in the treatment of major depressive disorder.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO CRD42021226161 .

Electric field-assisted multiphase extraction to increase selectivity and sensitivity in liquid chromatography-mass spectrometry and paper spray mass spectrometry

In this work, for the first time, chromatographic paper was used for a multiphase extraction assisted by an electric field (MPEF) and directly coupled to paper spray mass spectrometry (PS-MS). Using this approach, five tricyclic antidepressants (TCAs) were determined in oral fluid. Firstly, the MPEF conditions were optimized using liquid chromatography-mass spectrometry (LC-MS/MS). The effects of the chromatographic paper and the types of electrolyte used in the acceptor phase, the organic solvent type and the amount used in the donor phase, the extraction time, and the applied electric potential were all investigated. After optimization, the analytes were extracted from the donor solution (sample and acetonitrile 1:1 (v/v)) over a period of 10 min at 300 V, crossing the free liquid membrane (1-octanol) and reaching the acceptor phase (chromatographic paper wetted with 400 mmol L^-1 acetic acid). The method using LC-MS/MS was validated, demonstrating a linear range from 2 to 12 ng mL^-1, with detection and quantification limits of 0.13-0.25 and 0.44-0.84 ng mL^-1, respectively, an intraday precision of less than 20%, and no matrix effect observed. The optimized MPEF conditions were then applied to determine TCAs by PS-MS and for this analysis cyclobenzaprine was used as an internal standard. The easy, fast and direct approach of coupling MPEF with PS-MS analysis, as well as the pre-concentration and the low standard deviation of replicates (less than 20%), demonstrates that this method can be useful for screening in clinical and toxicological analysis.

A data visualisation method for assessing exposure misclassification in case-crossover studies: the example of tricyclic antidepressants and the risk of hip fracture in older people

Background

The case-crossover design is suited to medication safety studies but is vulnerable to exposure misclassification. Using the example of tricyclic antidepressants and the risk of hip fracture, we present a data visualisation tool for observing exposure misclassification in case-crossover studies.

Methods

A case-crossover study was conducted using Australian Government Department of Veterans’ Affairs claims data. Beneficiaries aged over 65 years who were hospitalised for hip fracture between 2009 and 2012 were included. The case window was defined as 1–50 days pre fracture. Control window one and control window two were defined as 101–150 and 151–200 days pre fracture, respectively. Patients were stratified by whether exposure status changed when control window two was specified instead of control window one. To visualise potential misclassification, each subject’s tricyclic antidepressant dispensings were plotted over the 200 days pre fracture.

Results

The study population comprised 8828 patients with a median age of 88 years. Of these subjects, 348 contributed data to the analyses with either control window. The data visualisation suggested that 14% of subjects were potentially misclassified with control window one while 45% were misclassified with control window two. The odds ratio for the association between tricyclic antidepressants and hip fracture was 1.18 (95% confidence interval = 0.91–1.52) using control window one, whereas risk was significantly increased (odds ratio = 1.43, 95% confidence interval = 1.11–1.83) using control window two.

Conclusions

Exposure misclassification was less likely to be present with control window one than with an earlier control window, control window two. When specifying different control windows in a case-crossover study, data visualisation can help to assess the extent to which exposure misclassification may contribute to variable results.

Analysis of the analgesic effects of tricyclic antidepressants on neuropathic pain, diabetic neuropathic pain, and fibromyalgia in rat models

OBJECTIVE

To investigate the analgesic effect of amitriptyline on neuropathic pain model rats, diabetic neuropathic pain model rats and fibromyalgia model rats.

METHODS

The healthy male Sprague wrote - Dawley (SD) rats were taken as the research object, and they were randomly divided into model group (group A), beside the sciatic nerve and injection of 5 mm amitriptyline group (group B), beside the sciatic nerve and injection of 10 mm amitriptyline group (group C), beside the sciatic nerve and injection of 15 mm amitriptyline group (group D), intraperitoneal injection of amitriptyline group (group E). Pain induced by selective injury of sciatic nerve branches in rats, pain induced by chronic compression of sciatic nerve, diabetic neuropathic pain and fibromyalgia were conducted to determine the pain threshold of mechanical stimulation in rats after drug administration.

RESULTS

The pain threshold of mechanical stimulation in the local amitriptyline group (group B, C, D) was significantly higher than that in the group A and group E at each time point after drug treatment, and the pain threshold of mechanical stimulation gradually increased with the increase of concentration. There was no statistically significant difference in mechanical stimulation pain threshold between group A and group E at each time point after drug treatment.

CONCLUSION

Para-sciatic injection of amitriptyline at different concentrations has analgesic effects on neuropathic pain, diabetic neuropathic pain and fibromyalgia in rat models, and amitriptyline directly ACTS on the local sciatic nerve.

β-Cyclodextrin Inclusion Complexation With Tricyclic Antidepressants Desipramine and Imipramine: A Structural Chemistry Perspective

Single-crystal X-ray diffraction and DFT calculation have been carried out for an atomic-level understanding of β-cyclodextrin (β-CD) inclusion complexation with 2 tricyclic antidepressants (TCAs), desipramine and imipramine. X-ray analysis discloses that the A-C-rings are buried in the β-CD cavity and the side chain is mostly outside the cavity, nearby the O2-H/O3-H side. Hence, the inclusion structures of both complexes are stabilized by host-guest C5-H∙∙∙π interaction and N5'-H∙∙∙O5/O6 H-bonds of twofold-screw-symmetry-related molecules, which are similar to those of the reported complexes of nortriptyline and amitriptyline. The DFT full-geometry optimization in the gas phase reveals an alternative inclusion scenario with the TCA side chain that is embedded in the β-CD cavity and stabilized by intermolecular O6-H∙∙∙N5' H-bond and O2-H/O3-H∙∙∙π interactions. The β-CD encapsulation of the TCA side chain is more energetically stable by 10.76 and 4.70 kcal mol^-1 than that of the aromatic moiety for the respective complexes of DPM and IPM, based on the relative stabilization energies (ΔΔE_stb). This suggests the existence of the bimodal β-CD-TCA inclusion complexes as spectroscopically observed in solution, thus explaining the controversy in the inclusion mode and the improvement of TCA therapeutic effect by CD encapsulation.

Antidepressants: bleeding or thrombosis?

The contribution of depression to the pathogenesis of cardiovascular disease includes autonomic disturbances, endothelial dysfunction, inflammation, smoking, sedentary lifestyle, carbohydrate craving, and impaired fibrinolysis. There is evidence that serotonergic antidepressants (selective serotonin reuptake inhibitors and serotonin and noradrenaline reuptake inhibitors) restore the fibrinolytic profile. Contrary to common belief, such antidepressants do not affect platelet aggregation induced by adenosine diphosphate or adrenaline but reduce platelet adhesion to collagen. Since platelet collagen receptor glycoprotein VI binds to fibrin, it is possible that fibrinolytic properties of serotonergic antidepressants could impair platelet adhesion to collagen. The profibrinolytic and antiplatelet properties of serotonergic antidepressants help explain the increased risk of gastrointestinal, intracranial, and surgical bleeding in patients using these medications. Studies evaluating the impact of antidepressants on thrombotic and cardiovascular risk have yielded contradictory results. Corroborating the hypothesis that serotonergic antidepressants have profibrinolytic and antiplatelet properties, some authors showed that these medications prevent both cardiovascular and thromboembolic events. Others showed an increased risk of ischemic stroke, cardiac events and thromboembolic disease. Silent brain infarction may present in some elders with depressive symptoms, so it is presumed that antidepressants are prescribed for subclinical stroke patients. Another explanation for the increased risk of cardiovascular and thromboembolic events reported by some authors in individuals taking antidepressants includes antidepressant side effects such as sedation and weight gain and depression comorbidities such as anxiety, obesity and hyperhomocysteinemia. In conclusion, we suggest that serotonergic antidepressants be considered weak anticoagulants. We also suggest that depressed patients with comorbidities increasing the risk of cardiovascular and thromboembolic disease be recommended to follow a balanced diet and engage in physical activity, such as daily walking.

β-Cyclodextrin encapsulation of nortriptyline HCl and amitriptyline HCl: Molecular insights from single-crystal X-ray diffraction and DFT calculation

The β-CD encapsulation of two tricyclic antidepressants (TCAs), nortriptyline (NRT) HCl and amitriptyline (AMT) HCl (most widely used TCA), has been thoroughly investigated by single-crystal X-ray diffraction and DFT calculation for insights into the inclusion complexation. X-ray analysis reveals that both drugs insert the A-ring moiety vertically from the β-CD O2H/O3H-side and are kept in position by C5H⋯π interactions, yielding thermodynamically favorable complexes. In the β-CD cavity, NRT and AMT are less open as their butterfly angles are ~10° smaller than those in free HCl salt forms and in complex with proteins. The effect of HCl salt on both complexes is evaluated by DFT full-geometry optimization. When Cl^- is directly linked with the NRT NH₂Me⁺ group, the inclusion complex formed gains stability by 3.65 kcal mol^-1 through N5'H⋯Cl⋯HO26 H-bond chain, compared to the complex of NRT base. The addition of HCl to N5' of the side chain marginally affects the structures of β-CD-TCA complexes. This study provides a rigorous crystallographic evidence for the β-CD-TCA complexation and a theoretical view on the improved stability of TCA in the CD cavity, supporting the pharmacological benefit of CD encapsulation in reducing the TCA side effects.

Use of Antidepressants and Risk of Incident Stroke: A Systematic Review and Meta-Analysis

BACKGROUND

Both depression and use of antidepressants have been reported to be risk factors for stroke, but results from the literature are still not conclusive regarding the risk attributable to antidepressants rather than to the underlying disease.

OBJECTIVE

To estimate the risk of incident stroke associated with use of antidepressants, a meta-analysis was performed.

METHODS

PubMed, Medline, Cochrane, ProQuest, Scopus, and bibliographies of articles were searched up to September 2018. The final meta-analysis included 31 observational studies. STROBE statement-checklist and GRADE guidelines were used for quality assessment.

RESULTS

The random-effects meta-analysis on the association between use of any antidepressant and risk of any stroke resulted in meta-risk ratio (RR) of 1.41 (95% CI 1.13-1.69, I2 = 93, 7%). The pooled estimate for selective serotonin reuptake inhibitors (SSRIs) resulted in a meta-RR of 1.41 (95% CI 1.13-1.69, I2 = 94, 5%) and for tricyclic antidepressants (TCAs) of 1.08 (95% CI 0.93-1.22, I2 = 0%). SSRI users displayed a higher risk of ischemic (1.57, 95% CI 1.06-2.09, I2 = 96.4%) than hemorrhagic stroke (1.34, 95% CI 1.15-1.53, I2 = 72.9%). Meta-RRs were lower for TCA, although with smaller heterogeneity (ischemic 1.22, 95% CI 0.97-1.46; I2 = 0%; hemorrhagic: 1.00, 95% CI 0.83-1.18, I2 = 0%). Restricting to studies on depressed individuals, both SSRI and TCA remained associated with an increased risk of any stroke type (meta-RR for SSRI: 1.27, 95% CI 1.11-1.43, I2 = 76.6%; meta-RR for TCA: 1.21 (95% CI 1.02-1.40, I2 = 47, 3%).

CONCLUSIONS

Despite the high heterogeneity, these results demonstrate that even after adjusting for depression, use of antidepressants retains an independent increased risk of stroke.

Electrochemical Behavior and Highly Sensitive Voltammetric Determination of Doxepin in Pharmaceutical Preparations and Blood Serum Using Carbon Ionic Liquid Electrode

In this manuscript, the electrocatalytic oxidation of doxepin (DOX) was studied at a carbon ionic liquid electrode, fabricated using graphite, and the ionic liquid 1-octylpyridinium hexaflourophosphate (OPFP). The surface of the proposed electrode was characterized by scanning electron microscopy. Differential pulse voltammetry was applied as an analytical technique for quantification of sub-micromolar concentration of doxepin. Various parameters were optimized for practical application. Under the optimal conditions, the proposed electrode exhibited interesting sensitivity toward determination of doxepin compared to the other conventional electrodes and the anodic peak current versus doxepin concentration was linear in the ranges of 0.05-24 µM. The detection limit of 21 nM was achieved. Cyclic voltammetry (CV) was also applied to acquire information about the reaction mechanism and calculating the kinetic parameters. The electroxidation process was irreversible and revealed adsorption controlled behavior. The method was successfully applied for determination of doxepin content in pharmaceuticals and blood serum samples.

Estimating environmental fate of tricyclic antidepressants in wastewater treatment plant

TCAs are known to be toxicants and endocrine disrupting agents. Generally, after being used, TCAs are passed through wastewater treatment plants (WWTPs) to be treated. However, still trace amounts (ng/L to μg/L) of TCAs have been founded even in the treated water. Therefore, the aim of this study is to elucidate the environmental behaviors of TCAs in the sewage water from WWTPs (Jeonju, Korea). For the experiments, seven TCAs (amitriptyline, imipramine, clomipramine, desipramine, protriptyline, nortriptyline, and doxepin) were selected. Hydrolysibility, biodegradability, and adsorbability of the selected seven TCAs were evaluated. Based on the results, it was concluded that TCAs are not readily hydrolyzed in water and also not biodegraded by aerobic sludge. The 60% to 85% of TCAs were adsorbed immediately onto the activated sludge within 1 s via electrostatic and hydrophobic interactions. It was clearly observed that adsorption affinities were dependent on the types of activated sludge (i.e. anaerobic and aerobic sludge). The affinities of aerobic and anaerobic sludge towards the TCAs at trace concentrations e.g., 1 to 10 μg/L, were estimated to be in the range from 0.021 ± 0.000 to 0.087 ± 0.000 L/μg and from 0.001 ± 0.000 to 0.108 ± 0.001 L/μg, respectively.

Anesthetic Considerations for Patients on Antidepressant Therapy-Part I

Millions of patients take antidepressant medications in the United States for the treatment of depression or anxiety disorders. Some antidepressants are prescribed off-label to treat problems such as chronic pain, low energy, and menstrual symptoms. Antidepressants are a broad and expansive group of medications, but the more common drug classes include tricyclic antidepressants, selective serotonin reuptake inhibitors, serotonin-norepinephrine reuptake inhibitors, and monoamine oxidase inhibitors. A miscellaneous or "atypical" category covers other agents. Some herbal supplements that claim to have antidepressant activity will also be discussed. In Part I of this review, antidepressant pharmacology, adverse effects, and drug interactions with adrenergic agonists will be discussed. In part II, drug interactions with sedation and general anesthetics will be reviewed. Bleeding effects and serotonin syndrome implications in anesthetic practice will also be highlighted.

Detection of potential risks in the prescription of tricyclic antidepressants through an online clinical alert system

OBJECTIVE

To analyse the use, indications and potential risks of tricyclic antidepressants (TCAs), using a technological system of clinical alerts at the time of prescription.

METHODS

Observational, descriptive, retrospective study on a population covered by a Colombian health insurance plan with an average of 2,333,582 members/month. The information was generated in the PBM (Pharmacy Benefit Management) MC21 Colombia technological platform.

RESULTS

Of the total members, 368,298 (16%) patients/month on average were prescribed medicines; 3,640 (1%) were prescribed TCAs: 2,573 amitriptyline (70%) and 1.062 imipramine (29%); 817 (22.5%) were over 65 years of age. The median daily dose of amitriptyline and imipramine was 25 mg. A total of 17,153 alerts were reported: 8,685 (51%) for drug-drug interactions, 7,354 (43%) for drug-age interactions and 543 (3%) for duplicate therapy.

CONCLUSIONS

Risks were identified in the prescription of tricyclic antidepressants, especially in the over-65 population, where these drugs are used in particular for the management of neuropathic pain. The clinical alert system at the time of medicinal product formulation can make an important contribution to the prevention of potential adverse events associated with the use of medicinal products.

Magnetic framework composite as sorbent for magnetic solid phase extraction coupled with high performance liquid chromatography for simultaneous extraction and determination of tricyclic antidepressants

In this study, magnetic framework composites (MFCs) (Fe₃O₄@TMU-10) microspheres were successfully fabricated and applied as an effective sorbent for preconcentration of the two model tricyclic antidepressants (TCAs) amitriptyline and imipramine from biological samples. MFCs were fabricated by a step-by-step assembly, novel, simple and efficient strategy. The shell thickness of the Metal-organic frameworks (MOFs) could also be easily controlled by tuning the number of assembly cycles. By coupling magnetic solid-phase extraction (MSPE) with high-performance liquid chromatography with UV detector (HPLC-UV), a simple, reliable, fast, sensitive and cost-effective method for simultaneous determination of TCAs was developed. Under optimal conditions, the preconcentration factors and relative recoveries of the studied compounds were obtained in the range of 43-50 and 90.5-99.0% respectively. The calibration curves were obtained in the range of 5-800 μg L^-1 with reasonable linearity (R² > 0.9904) and the limits of detection (LODs) ranged between 2 and 4 μg L^-1 (based on S/N = 3). The relative standard deviations of intra- and inter-day tests ranged from 3.1 to 4.6% and from 4.3 to 5.2%, respectively. The results demonstrate that Fe₃O₄@TMU-10 core-shell magnetic microspheres combine advantages of MOFs and magnetic nanoparticles, and are the promising sorbents for rapid and efficient extraction of target analytes from urine and plasma complex biological samples.

The effect of intracerebroventricular allopregnanolone on depressive-like behaviors of rats selectively bred for high and low immobility in the forced swim test

Depression is a highly incapacitating disorder known to have a multifactorial etiology, including a hereditary genetic background. The neurosteroid allopregnanolone (ALLO) is a positive allosteric modulator of the GABA_A receptor and has been shown to have an antidepressant-like effect in animals. This study aimed to assess the behavioral effect of ALLO in animals with different backgrounds of depressive-like activity. An initial population (F0) of male and female Wistar rats was screened for immobility behavior utilizing the Forced Swim Test (FST). Rats with extreme immobility scores were selected for either the High Immobility (HI) group or the Low Immobility (LI) group for breeding, giving origin to the subsequent generations F1 and F2. Guide cannulas were implanted in the lateral ventricle of F2 males for intracerebroventricular infusions of 5 μg/rat of ALLO, 5 μg/rat of imipramine (IMI) or vehicle (CTR), which occurred 24, 5 and 1 h prior to the test session of the drug FST. In the pre-drug FST, a statistically significant difference was observed between the immobility scores from the HI and LI groups of F2 rats. HI rats from F2 also showed significantly higher immobility time when compared to F0. In these HI animals, both IMI and ALLO significantly reduced immobility when compared to the CTR group. IMI-treated rats also showed lower immobility than the ALLO group. In the LI rats, no difference in immobility was found between treatments. In conclusion, two strains of rats with significantly different immobility profiles in the FST were obtained in a relatively short time, after only two generations. Infusions of both ALLO and IMI showed a strain-dependent antidepressant-like effect, being detected in the HI animals but not in the LI animals, which is in line with the clinical understanding that antidepressants have higher efficacy in more severe forms of depression.

Medication for Behavior Modification in Birds

The use of behavior modifying drugs may be considered in birds with behavior problems, especially those refractory to behavior modification therapy and environmental management. To accomplish behavior change, a variety of drugs can be used, including psychoactive drugs, hormones, antihistamines, analgesics, and anticonvulsants. Because their prescription to birds is off-label, these drugs are considered appropriate only when a sound rationale can be provided for their use. This requires a (correct) behavioral diagnosis to be established. In addition, regular monitoring and follow-up are warranted to determine the efficacy of the treatment and evaluate the occurrence of potential adverse side effects.

Tricyclic antidepressants inhibit hippocampal α7* and α9α10 nicotinic acetylcholine receptors by different mechanisms

The activity of tricyclic antidepressants (TCAs) at α7 and α9α10 nicotinic acetylcholine receptors (AChRs) as well as at hippocampal α7-containing (i.e., α7*) AChRs is determined by using Ca²⁺ influx and electrophysiological recordings. To determine the inhibitory mechanisms, additional functional tests and molecular docking experiments are performed. The results established that TCAs (a) inhibit Ca²⁺ influx in GH3-α7 cells with the following potency (IC₅₀ in μM) rank: amitriptyline (2.7 ± 0.3) > doxepin (5.9 ± 1.1) ∼ imipramine (6.6 ± 1.0). Interestingly, imipramine inhibits hippocampal α7* AChRs (42.2 ± 8.5 μM) in a noncompetitive and voltage-dependent manner, whereas it inhibits α9α10 AChRs (0.53 ± 0.05 μM) in a competitive and voltage-independent manner, and (b) inhibit [³H]imipramine binding to resting α7 AChRs with the following affinity rank (IC₅₀ in μM): imipramine (1.6 ± 0.2) > amitriptyline (2.4 ± 0.3) > doxepin (4.9 ± 0.6), whereas imipramine's affinity was no significantly different to that for the desensitized state. The molecular docking and functional results support the notion that imipramine noncompetitively inhibits α7 AChRs by interacting with two overlapping luminal sites, whereas it competitively inhibits α9α10 AChRs by interacting with the orthosteric sites. Collectively our data indicate that TCAs inhibit α7, α9α10, and hippocampal α7* AChRs at clinically relevant concentrations and by different mechanisms of action.

Tricyclic Antidepressants and Monoamine Oxidase Inhibitors: Are They Too Old for a New Look?

Through unintentional discovery, monoamine oxidase inhibitors (MAOIs) and tricyclic antidepressants (TCAs) were the first antidepressant classes to be used clinically and have been widely available for over half a century. From the 1950s to the 1980s, these two classes of antidepressants were the sole antidepressant tools available to psychiatrists. With the advent of the selective serotonin reuptake inhibitors (SSRIs) in the 1980s and 1990s, the prescribing of the MAOIs and TCAs has fallen significantly worldwide. In this chapter, we take a closer look at the arc of MAOI discovery and clinical use, and how these two classes of drugs compare to each other. This is important because relatively few studies compare these older classes of drugs to the newer classes of antidepressants. Finally, we argue that TCAs, and particularly MAOIs, should continue to play an important role in the modern treatment of depression, especially in the treatment-resistant patient.

Pharmacotherapy for Neuropathic Pain: A Review

Abstract

Neuropathic pain, comprising a range of heterogeneous conditions, is often severe and difficult to manage, and this may result in a chronic condition that negatively affects the overall functioning and quality of life in patients. The pharmacotherapy of neuropathic pain is challenging and for many patients effective treatment is lacking; therefore, evidence-based recommendations are essential. Currently, there is general agreement on which drugs are appropriate for the first-line treatment of neuropathic pain, whereas debate continues regarding second- and third-line treatments. First-line drugs for neuropathic pain include antidepressants (tricyclic antidepressants and serotonin–noradrenaline reuptake inhibitors) and anticonvulsants acting at calcium channels (pregabalin and gabapentin). Second- and third-line drugs for neuropathic pain include topical lidocaine and opioids. Although efficacious in the treatment of neuropathic pain, opioids are not considered to be a first choice because of adverse drug reactions and, more recently, because of concerns about abuse, diversion, and addiction. A clear understanding of the mechanism of action of currently available drugs is an essential step towards an effective clinical approach that aims to tailor therapies both to the specific neuropathic disease and to the needs of an individual patient. This review provides an overview of current drugs available for the treatment of neuropathic pain with an emphasis on their mechanism of action.

Funding

Pfizer, Italy.

Antidepressants and the risk of arrhythmia in elderly affected by a previous cardiovascular disease: a real-life investigation from Italy

PURPOSE

The study aimed to fill existing knowledge gaps on the safety of antidepressant drugs (ADs) by estimating the risk of hospitalization for arrhythmia associated with use of selective serotonin reuptake inhibitors (SSRIs) and newer atypical ADs (NAAs) among elderly with previous cardiovascular (CV) events.

METHODS

The cohort was composed by 199,569 individuals aged ≥ 65 years from five Italian healthcare territorial units who were discharged for cardiovascular outcomes in the years 2008-2010. The 17,277 patients who experienced hospital admission for arrhythmia during follow-up were included as cases. Odds of current ADs use among cases (i.e., 14 days before hospital admission) was compared with (i) odds of current use of 1:5 matched controls (between-patients case-control) and with (ii) odds of previous use during 1:5 matched control periods (within-patient case-crossover). The risk of arrhythmia associated with ADs current use was modelled fitting a conditional logistic regression. A set of sensitivity analyses was performed to account for sources of systematic uncertainty.

RESULTS

Current users of SSRIs and NAAs were at increased risk of arrhythmia with case-control odds ratios (OR) of 1.37 (95% confidence interval, CI 1.18 to 1.58) and 1.41 (1.16 to 1.71) and case-crossover OR of 1.48 (1.20 to 1.81) and 1.72 (1.31 to 2.27). An increased risk of arrhythmia was associated with current use of trazodone (NAA) consistently in case-control and case-crossover designs.

CONCLUSIONS

Evidence that current use of SSRIs and NAAs is associated to an increased risk of arrhythmia among elderly with CV disease was consistently supplied by two observational approaches.

Antidepressants inhibit Nav1.3, Nav1.7, and Nav1.8 neuronal voltage-gated sodium channels more potently than Nav1.2 and Nav1.6 channels expressed in Xenopus oocytes

Tricyclic antidepressants (TCAs) and duloxetine are used to treat neuropathic pain. However, the mechanisms underlying their analgesic effects remain unclear. Although many investigators have shown inhibitory effects of antidepressants on voltage-gated sodium channels (Na_v) as a possible mechanism of analgesia, to our knowledge, no one has compared effects on the diverse variety of sodium channel α subunits. We investigated the effects of antidepressants on sodium currents in Xenopus oocytes expressing Na_v1.2, Na_v1.3, Na_v1.6, Na_v1.7, and Na_v1.8 with a β₁ subunit by using whole-cell, two-electrode, voltage clamp techniques. We also studied the role of the β₃ subunit on the effect of antidepressants on Na_v1.3. All antidepressants inhibited sodium currents in an inactivated state induced by all five α subunits with β₁. The inhibitory effects were more potent for Na_v1.3, Na_v1.7, and Na_v1.8, which are distributed in dorsal root ganglia, than Na_v1.2 and Na_v1.6, which are distributed primarily in the central nervous system. The effect of amitriptyline on Na_v1.7 with β₁ was most potent with a half-maximal inhibitory concentration (IC₅₀) 4.6 μmol/L. IC₅₀ for amitriptyline on Na_v1.3 coexpressed with β₁ was lowered from 8.4 to 4.5 μmol/L by coexpression with β₃. Antidepressants predominantly inhibited the sodium channels expressed in dorsal root ganglia, and amitriptyline has the most potent inhibitory effect. This is the first evidence, to our knowledge, showing the diverse effects of antidepressants on various α subunits. Moreover, the β₃ subunit appears important for inhibition of Na_v1.3. These findings may aid better understanding of the mechanisms underlying the pain relieving effects of antidepressants.

Amitriptyline-induced ventricular tachycardia: a case report

Background

In Bangladesh, each emergency physician faces amitriptyline overdose nearly a day. An acute cardiovascular complication, one of the worst complications is mainly responsible for the mortality in tricyclic overdose. Recently, we managed ventricular tachycardia in a young female presented with an impaired consciousness 10 h after intentionally ingesting 2500 mg amitriptyline. Here, we report it, discuss how the electrocardiography is vital to acknowledge and predict it and its’ complications and also the recent update of the management of it.

Case presentation

A young married Bangladeshi-Bengali girl, 25-year-old, having a history of disharmony with her husband, came with an impaired consciousness after intentionally ingesting 2500 mg amitriptyline about 10 h before arrival. There was blood pressure 140/80 mmHg, heart rate 140 beats-per-min, temperature 103 °F, Glasgow coma scale 10/15, wide complex tachycardia with QRS duration of 178 ms in electrocardiography, blood pH 7.36. Initially, treated with 100 ml 8.4% sodium bicarbonate. After that, QRS duration came to 100 ms in electrocardiography within 10 min of infusion. To maintain the pH 7.50–7.55 over the next 24 h, the infusion of 8.4% sodium bicarbonate consisting of 125 ml dissolved in 375 ml normal saline was started and titrated according to the arterial blood gas analysis. Hence, a total dose of 600 mmol sodium bicarbonate was given over next 24 h. In addition to this, gave a 500 ml intravenous lipid emulsion over 2 h after 24 h of admission as she did not regain her consciousness completely. Afterward, she became conscious, though, in electrocardiography, ST/T wave abnormality persisted. So that, we tapered sodium bicarbonate infusion slowly and stopped it later. At the time of discharge, she was by heart rate 124/min, QRS duration 90 ms in electrocardiogram along with other normal vital signs.

Conclusion

Diagnosis of amitriptyline-induced ventricular tachycardia is difficult when there is no history of an overdose obtained. Nevertheless, it should be performed in the clinical background and classic electrocardiographic changes and wise utilization of sodium bicarbonate, intravenous lipid emulsion, and anti-arrhythmic drugs may save a life.

Role of cortical alpha-2 adrenoceptors in alcohol withdrawal-induced depression and tricyclic antidepressants

INTRODUCTION

Although a role for alpha-2 adrenoceptors (alpha-2 ARs) in alcohol use disorder (AUD) and depression is suggested, very little information on a direct interaction between alcohol and these receptors is available.

METHODS

In this study adult female Wistar and Wistar-Kyoto (WKY) rats, a putative animal model of depression, were exposed to alcohol vapor 3h daily for 10days (blood alcohol concentration ∼150mg%) followed by daily injection of 10mg/kg of imipramine (IMP, a selective norepinephrine NE/serotonin reuptake inhibitor) or nomifensine (NOMI, a selective NE/dopamine reuptake inhibitor). On day 11 animals were tested for open field locomotor activity (OFLA) and forced swim test (FST) and were sacrificed 2h later for measurement of alpha-2 ARs densities in the frontal cortex and hippocampus using [3H]RX 821002 as the specific ligand.

RESULTS

Chronic alcohol treatment increased the immobility in the FST, without affecting OFLA in both Wistar and WKY rats, suggesting induction of depressive-like behavior in Wistar rats and an exacerbation of this behavior in WKY rats. Alcohol treatment also resulted in an increase in cortical but not hippocampal alpha-2 ARs densities in both Wistar and WKY rats. The behavioral effects of alcohol were completely blocked by IMP and NOMI and the neurochemical effects (increases in alpha-2 ARs) were significantly attenuated by both drugs in both strains.

CONCLUSIONS

The results suggest a role for cortical alpha-2 ARs in alcohol withdrawal-induced depression and that selective subtype antagonists of these receptors may be of adjunct therapeutic potential in AUD-depression co-morbidity.

A Literature Review of the Use of Sodium Bicarbonate for the Treatment of QRS Widening

Sodium bicarbonate is a well-known antidote for tricyclic antidepressant (TCA) poisoning. It has been used for over half a century to treat toxin-induced sodium channel blockade as evidenced by QRS widening on the electrocardiogram (ECG). The purpose of this review is to describe the literature regarding electrophysiological mechanisms and clinical use of this antidote after poisoning by tricyclic antidepressants and other agents. This article will also address the literature supporting an increased serum sodium concentration, alkalemia, or the combination of both as the responsible mechanism(s) for sodium bicarbonate's antidotal properties. While sodium bicarbonate has been used as a treatment for cardiac sodium channel blockade for multiple other agents including citalopram, cocaine, flecainide, diphenhydramine, propoxyphene, and lamotrigine, it has uncertain efficacy with bupropion, propranolol, and taxine-containing plants.

Cardiotoxicity of tricyclic antidepressant treated by 2650 mEq sodium bicarbonate: A case report

Poisoning with tricyclic antidepressants is an important cause of drug-related self-poisoning in the developed world and a very common cause of poisoning and mortality in developing countries. Electrocardiographic manifestations of most tricyclic antidepressant-poisoned patients resolve by the administration of 1-2 mEq/kg of sodium bicarbonate. Some rare cases have been reported who have been resistant to the long-term or high doses of bicarbonate administration. We present a case of acute tricyclic antidepressant toxicity referring with status epilepticus, hypotension, and refractory QRS complex widening that resolved after the intravenous administration of 2650 mEq sodium bicarbonate.

Dispersive liquid-liquid microextraction combined with acetonitrile stacking through capillary electrophoresis for the determination of three selective serotonin reuptake inhibitor drugs in body fluids

Dispersive liquid-liquid microextraction was combined with acetonitrile stacking in capillary electrophoresis for the identification of three selective serotonin reuptake inhibitors (citalopram, fluoxetine, and fluvoxamine) in human fluids such as urine and plasma. Parameters that affect the extraction and stacking efficiency, such as the type and volume of the extraction and disperser solvent, extraction time, salt addition for dispersive liquid-liquid microextraction, and sample matrices, pH, and concentration of the separation buffer for stacking, were investigated and optimized. Under optimum conditions, the enrichment factors were in the range of 1195-1441. Limits of detection ranged from 1.4 to 1.7 nM for the target analytes. Calibration graphs displayed satisfied linearity with R² greater than or equal to 0.9978, and relative standard deviations of the peak area analysis were in the range of 2.9-5.0% (n = 3). The recoveries of all tricyclic antidepressant drugs from urine and plasma were in the range of 77-117 and 79-106%, respectively. The findings of this study show that dispersive liquid-liquid microextraction acetonitrile-stacking capillary electrophoresis is a rapid and convenient method for identifying tricyclic antidepressant drugs in urine and plasma.

Novel Treatments for Cyclic Vomiting Syndrome: Beyond Ondansetron and Amitriptyline

OPINION STATEMENT

Cyclic vomiting syndrome (CVS) is a chronic functional gastrointestinal disorder that is characterized by episodic nausea and vomiting. Initially thought to only affect children, CVS in adults was often misdiagnosed with significant delays in therapy. Over the last decade, there has been a considerable increase in recognition of CVS in adults but there continues to be a lack of knowledge about management of this disorder. This paper seeks to provide best practices in the treatment of CVS and also highlight some novel therapies that have the potential in better treating this disorder in the future. Due to the absence of randomized control trials, we provide recommendations based on review of the available literature and expert consensus on the therapy of CVS. This paper will discuss prophylactic and abortive therapy and general measures used to treat an episode of CVS and also discuss pathophysiology as it pertains to novel therapy. Recent recognition of the association of chronic marijuana use with cyclic vomiting has led to the possibility of a new diagnosis called "Cannabinoid Hyperemesis Syndrome," which is indistinguishable from CVS. The treatment for this purported condition is abstinence from marijuana despite scant evidence that marijuana use is causative. Hence, this review will also discuss emerging data on the role for the endocannabinoid system in CVS and therapeutic agents targeting the endocannabinoid system, which offer the potential of transforming the care of these patients.

Analysis of tricyclic antidepressants in human plasma using online-restricted access molecularly imprinted solid phase extraction followed by direct mass spectrometry identification/quantification

The use of a new class of hybrid materials, called restricted access molecularly imprinted polymers (RAMIPs) seems to present a good strategy for the sample preparation of complex matrices, since these materials combine good protein elimination capacity with high degree selectivity. Mass spectrometers (MS) have been successfully used for polar drug identification and quantification. In order to combine the advantages of both RAMIPs and mass spectrometry, we proposed a study that joins these properties in a single system, where we could analyse tricyclic antidepressants from human plasma, without offline extraction or chromatographic separation. A RAMIP for amitriptyline was synthesised by the bulk method, using methacrylic acid as a functional monomer and glycidilmethacrylate as a hydrophilic co-monomer. Then, epoxide ring openings were made and the polymer was covered with bovine serum albumin (BSA). A column filled with RAMIP-BSA was coupled to a MS/MS instrument in an online configuration, using water as loading and reconditioning mobile phase and a 0.01% acetic acid aqueous solution: acetonitrile at 30:70 as elution mobile phase. The system was used for on-line extraction and simultaneous quantification of nortriptyline, desipramine, amitriptyline, imipramine, clomipramine and clomipramine-d3 (IS) (from 15.0 to 500.0μgL^-1) from plasma samples. The correlation coefficient was higher than 0.99 for all analytes. The CV (coefficient of variation) values ranged from 1.34% to 19.13% for intra assay precision and 1.32-19.77% for inter assay precision. The E% (relative error) values ranged from -19.15% to 19.51% for intra assay accuracy and from -9.04% to 16.22% for inter assay accuracy.

Quantification of Tricyclic Antidepressants in Serum Using Liquid Chromatography Electrospray Tandem Mass Spectrometry (HPLC-ESI-MS/MS)

Tricyclic antidepressants (TCA) are used to treat major depressive disorder and other psychological conditions. The efficacy of these drugs is tied to a narrow therapeutic window. Inappropriately high drug concentrations can result in serious side effects such as hypotension, tachycardia, or coma. As a result, concentrations of tricyclic antidepressants are routinely monitored to ensure compliance and to prevent adverse side effects by dose adjustments. We describe a method for the determination of concentrations of amitriptyline, desipramine, imipramine, and nortriptyline in human serum using high-performance liquid chromatography coupled to a tandem mass spectrometer with electrospray ionization (HPLC-ESI-MS/MS). The method is rapid, requiring only 3.5 min per analysis. The method requires 100 μL of serum. Concentrations of each TCA were quantified by a calibration curve relating the peak area ratio of each TCA analyte to a deuterated internal standard (amitriptyline-D3, desipramine-D3, imipramine-D3, and nortriptyline-D3). The method was linear from ~70 ng/mL to ~1000 ng/mL for all TCAs, with imprecision ≤ 12%.

UV-photodegradation of desipramine: Impact of concentration, pH and temperature on formation of products including their biodegradability and toxicity

Desipramine (DMI) is a widely used tricyclic antidepressant, and it is the major metabolite of imipramine (IMI) and lofepramine (LMI); IMI and LMI are two of the most commonly used tricyclic antidepressants. If DMI enters the aquatic environment, it can be transformed by the environmental bacteria or UV radiation. Therefore, photolysis of DMI in water was performed using a simulated sunlight Xenon-lamp and a UV-lamp. Subsequently, the biodegradability of DMI and its photo-transformation products (PTPs) formed during its UV photolysis was studied. The influence of variable conditions, such as initial DMI concentration, solution pH, and temperature, on DMI UV photolysis behavior was also studied. The degree of mineralization of DMI and its PTPs was monitored. A Shimadzu HPLC-UV apparatus was used to follow the kinetic profile of DMI during UV-irradiation; after that, ion-trap and high-resolution mass spectrometry coupled with chromatography were used to monitor and identify the possible PTPs. The environmentally relevant properties and selected toxicity properties of DMI and the non-biodegradable PTPs were predicted using different QSAR models. DMI underwent UV photolysis with first-order kinetics. Quantum yields were very low. DOC values indicated that DMI formed new PTPs and was not completely mineralized. Analysis by means of high-resolution mass spectrometry revealed that the photolysis of DMI followed three main photolysis pathways: isomerization, hydroxylation, and ring opening. The photolysis rate was inversely proportional to initial DMI concentration. The pH showed a significant impact on the photolysis rate of DMI, and on the PTPs in terms of both formation kinetics and mechanisms. Although temperature was expected to increase the photolysis rate, it showed a non-significant impact in this study. Results from biodegradation tests and QSAR analysis revealed that DMI and its PTPs are not readily biodegradable and that some PTPs may be human and/or eco-toxic, so they may pose a risk to the environment.

Rising Trend of Use of Antidepressants Induced Non- Puerperal Lactation: A Case Report

Non puerperal lactation or galactorrhea is a well known side effect of antipsychotic drugs but has been infrequently described with the use of antidepressants. In past few decades, there have been emerging trend of isolated case reports of selective serotonin reuptake inhibitors induced non puerperal lactation. We report a case of non puerperal lactation following usage of second generation tricyclic antidepressant, nortriptyline and resolution on withdrawing the drug. Literature review has been done for antidepressant induced galactorrhea to understand the current trends, putative mechanism as different from one implicated for antipsychotics and its clinical utility.

REM sleep homeostasis in the absence of REM sleep: Effects of antidepressants

Most antidepressants suppress rapid eye movement (REM) sleep, which is thought to be important to brain function, yet the resulting REM sleep restriction is well tolerated. This study investigated the impact of antidepressants with different mechanisms of action, such as selective serotonin reuptake inhibitors (SSRIs) and tricyclic antidepressants (TCA), on the regulation of REM sleep in rats. REM sleep was first demonstrated to be homeostatically regulated using 5, 8 and 10 h of REM-sleep specific restriction through EEG-triggered arousals, with an average of 91 ± 10% of lost REM sleep recovered following a 26-29 -hour recovery period. Acute treatment with the antidepressants paroxetine, citalopram and imipramine inhibited REM sleep by 84 ± 8, 84 ± 8 and 69 ± 9% respectively relative to vehicle control. The pharmacologically-induced REM sleep deficits by paroxetine and citalopram were not fully recovered, whereas, after imipramine the REM sleep deficit was fully compensated. Given the marked difference between REM sleep recovery following the administration of paroxetine, citalopram, imipramine and REM sleep restriction, the homeostatic response was further examined by pairing REM sleep specific restriction with the three antidepressants. Surprisingly, the physiologically-induced REM sleep deficits incurred prior to suppression of REM sleep by all antidepressants was consistently recovered. The data indicate that REM sleep homeostasis remains operative following subsequent treatment with antidepressants and is unaffected by additional pharmacological inhibition of REM sleep.

Survival after severe amitriptyline poisoning with prolonged ventricular tachycardia and cardiac arrest

Background

Tricyclic antidepressants (TCA) are becoming one of the most frequently used substances in self poisoning. Significant morbidity and mortality associated with TCA overdose are often related to and refractory hypotension. We report the first case of survival after severe amitriptyline poisoning, leading to prolonged cardiac arrest and ventricular tachycardia (VT), resuscitated with 3 h of uninterrupted cardiac massage and Direct current (DC) shocks.

Case presentation

A 25 year old girl presented with severe amitriptyline poisoning causing pulseless VT and prolonged cardiac arrest. After 3 h of uninterrupted external cardiac massage, together with nine DC shocks and intra venous bicarbonate injections the rhythm reverted to a nodal tachycardia, initial 2D echocardiogram showed left ventricular dysfunction, which recovered to normal after 2 weeks and the patient had a complete recovery subsequently.

Conclusion

Our case highlights the importance of continued resuscitation in patients presenting with TCA poisoning and resistant arrhythmia, especially in young and otherwise healthy patients.