Alpha₂-adrenergic agonists for the management of opioid withdrawal

Blood pressure response to extended-release naltrexone in heroin and prescription opioid users and its implications for cardiovascular morbidity

BACKGROUND

Consuming opioid agonists is a risk factor for cardiovascular disease particularly in intravenous heroin users. The monthly injectable extended-release opioid antagonist, naltrexone (XR-NTX) is an effective treatment for opioid use disorder. The impact of opioid receptor blockade through XR-NTX on blood pressure, a critical risk factor for cardiovascular morbidity, has not yet been characterized.

METHODS

The study evaluated the change in blood pressure during XR-NTX treatment among 14 patients who predominately used intravenous heroin and 24 patients who used prescription oral opioids, all with opioid use disorder. Blood pressure was measured in each patient immediately before the first XR-NTX injection and ∼two weeks after the first injection. The change in diastolic and systolic pressure was compared between the heroin users and the prescription opioids users using analysis of variance.

RESULTS

XR-NTX treatment was associated with significant decreases in diastolic blood pressure in the heroin group, but not in the prescription opioids group. Systolic blood pressure values in the heroin users showed a decline at trend level only.

CONCLUSIONS

Further research is warranted to replicate our findings and to determine whether XR-NTX effect is relatively specific to blood pressure or generalizes to other components of metabolic syndrome. Distinguishing between heroin and prescription opioid users could shed light on the unique clinical and pharmacological profiles of opioid drugs, particularly regarding their cardiovascular safety. This information can be useful in developing personalized therapeutic strategies based on the route of opioid administration.

Discontinuation of psychotropic medication: a synthesis of evidence across medication classes

Pharmacotherapy is an effective treatment modality across psychiatric disorders. Nevertheless, many patients discontinue their medication at some point. Evidence-based guidance for patients, clinicians, and policymakers on rational discontinuation strategies is vital to enable the best, personalized treatment for any given patient. Nonetheless, there is a scarcity of guidelines on discontinuation strategies. In this perspective, we therefore summarize and critically appraise the evidence on discontinuation of six major psychotropic medication classes: antidepressants, antipsychotics, benzodiazepines, mood stabilizers, opioids, and stimulants. For each medication class, a wide range of topics pertaining to each of the following questions are discussed: (1) Who can discontinue (e.g., what are risk factors for relapse?); (2) When to discontinue (e.g., after 1 year or several years of antidepressant use?); and (3) How to discontinue (e.g., what's the efficacy of dose reduction compared to full cessation and interventions to mitigate relapse risk?). We thus highlight how comparing the evidence across medication classes can identify knowledge gaps, which may pave the way for more integrated research on discontinuation.

A Comprehensive Review of Novel FDA-Approved Psychiatric Medications (2018-2022)

Mental health disorders are among the top leading causes of disease burden worldwide and many patients have high levels of treatment resistance. Even though medications offer improvement to some patients, antidepressants are only effective in about half of those treated, and schizophrenia is treatment-refractory in about one-third of patients. One way to combat this disparity is to improve medication development and discovery for psychiatric disorders through evidence-based research. Recently, most psychiatric medications approved by the United States Food and Drug Administration (FDA) are for increased tolerability or extended release. Because of the slow, incremental progress, there is a pressing need to explore novel medications with new indications or mechanisms of action to treat the expanding population with mental disorders, especially in those who are fully or partially recalcitrant to first-line medication options. This review aims to present the newest FDA medications with new indications, establish the clinical need for each, and discuss future directions in drug development. We searched and reviewed novel psychiatric medications approved by the FDA from 2018 to 2022. We then analyzed each medication in the United States Clinical Trials Registry and gathered updated results for efficacy and safety information. We also searched PubMed/MEDLINE (Medical Literature Analysis and Retrieval System Online), Scopus, Web of Science, Elsevier, and Google Scholar to understand how these new indications met current clinical needs. Finally, we inquired about related technological implications that will lead the field of psychopharmacology now and in the years to come. We found 12 novel psychiatric medications approved by the FDA from 2018 to 2022, representing a very small percentage of the total FDA approvals during that period. These psychiatric medications with novel mechanisms or improved efficacy and safety  are expected to provide further options for treating mental health disorders; promising results will lead to new patterns of research.

Novel Use of Clonidine Patch to Treat Tizanidine Withdrawal

Tizanidine is commonly prescribed for muscle spasticity and pain. Yet, withdrawal is rarely reported. Tizanidine stimulates presynaptic α-2 adrenergic and imidazoline receptors decreasing norepinephrine release. Abrupt cessation can cause withdrawal. Current treatment strategies include tapering oral tizanidine or substituting oral clonidine. A 52-year-old male with a history of hypertension, diabetes, coronary artery disease, and chronic back pain presented with altered mental status, agitation, hypertensive emergency (blood pressure: 250/145 mmHg), and tachycardia. The patient had been prescribed tizanidine for chronic back pain for two years and had recently run out with suspicion of misuse. Tizanidine withdrawal was diagnosed, and he improved with 0.1 mg oral clonidine three times daily weaned over five days while hospitalized. One month later the patient was admitted for persistent hypertension, tachycardia, diaphoresis, and anxiety. Alpha-2 agonist withdrawal was again diagnosed. Utilizing a clonidine patch taper may offer a reasonable approach in patients with tizanidine withdrawal.

Guanfacine Treatment in a Patient with Intravenous Buprenorphine/Naloxone Misuse

In this case report, we described a patient admitted with buprenorphine/naloxone (BN) misuse, accompanied by intermittent pregabalin misuse, to self-treat the opioid withdrawal symptoms. We treated the withdrawal symptoms after cessation of BN with guanfacine extended-release (XR). To our knowledge, it has been the first case report describing guanfacine-XR in the treatment of BN misuse. Notably, our patient responded to the treatment with a decrease in withdrawal symptoms without any significant side-effect. Although it is not possible to generalize our findings with a single case report, it might be useful to mark guanfacin-XR as a potential treatment agent for opioid use disorders, including patients with synthetic opioid misuse.

Low dose lofexidine for medically directed outpatient opioid tapering in adults with chronic pain: a prospective case series

BACKGROUND

In adults with chronic pain, mild-to-moderate withdrawal symptoms during medically directed opioid tapering in the outpatient setting may not be accompanied by hypertension or tachycardia. This clinical scenario could limit the use of lofexidine at dosages reported in clinical trials of opioid withdrawal precipitated by abrupt opioid discontinuation. Thus, the primary aim of this prospective case series is to describe the use of low dose lofexidine for opioid withdrawal in patients with chronic pain undergoing medically directed opioid tapering in an outpatient setting.

METHODS

Six patients (white 5, Latino 1) admitted to an outpatient interdisciplinary pain rehabilitation program met inclusion and exclusion criteria. Patients self-selected to undergo medically directed opioid tapering, and the medication the patients were prescribed upon admission was used in the taper schedule. Upon initiation of the opioid taper, patients received 0.18 mg of lofexidine every 6 hours.

RESULTS

Five of the six patients were women, and the median morphine milligram equivalents at baseline were 36.9. The median taper duration was 15 days, and the median duration of lofexidine administration was 14 days. Withdrawal scores were mild throughout the taper in four patients, and two patients with fibromyalgia experienced single episodes of moderately severe withdrawal symptoms at the median morphine milligram equivalent midpoint of the taper. No hypotension or sustained bradycardia were observed, and no adverse effects related to lofexidine were reported.

CONCLUSION

The observations from this prospective case series suggest that low-dose lofexidine may be a feasible adjunct medication to attenuate withdrawal symptoms in adults with chronic pain undergoing outpatient opioid tapering.

Repeated measures analysis of opioid use disorder treatment on clinical opiate withdrawal scale in a randomized clinical trial: sex differences

PURPOSE

Sex differences may exist in opioid use disorder (OUD) treatment. This study examined the treatment effects of buprenorphine/naloxone (BUP/NX) and methadone (MET) on the Clinical Opiate Withdrawal Scale (COWS) score in individuals with OUD and tested whether the associations differ by sex.

METHOD

We performed a secondary analysis of the data from the National Drug Abuse Treatment Clinical Trials Network (CTN) protocol-0027. A total of 1269 participants (861 males and 408 females) being aged 18 or older with OUD were randomly assigned to receive BUP/NX (n = 740) or MET (n = 529). The paired t test was initially used to compare the COWS scores between pre-dose and post-dose for BUP/NX and MET treatments, separately. The linear mixed model was used to examine the changes in COWS score adjusted for baseline demographic, substance use, and mental health disorders. The interaction of sex and treatment was detected and stratified analysis by sex was conducted.

RESULTS

The paired t test showed that both BUP/NX and MET treatments significantly reduced the COWS scores (p values <0.0001). BUP/NX revealed higher COWS scores than MET (p = 0.0008) and females demonstrated significantly higher COWS scores than males (p = 0.0169). Stratified by sex, BUP/NX compared with MET revealed higher COWS scores only in males (p = 0.0043), whereas baseline amphetamines use disorder and major depressive disorder were significantly associated with COWS scores in females (p = 0.0158 and 0.0422, respectively).

CONCLUSIONS

Both BUP/NX and MET are effective in decreasing opioid withdrawal symptoms via COWS scores, however, treatment plans for OUD by clinical providers should consider sex differences.

Case report: The lesson from opioid withdrawal symptoms mimicking paraganglioma recurrence during opioid deprescribing in cancer pain

Pain is one of the predominant and troublesome symptoms that burden cancer patients during their whole disease trajectory: adequate pain management is a fundamental component of cancer care. Opioid are the cornerstone of cancer pain relief therapy and their skillful management must be owned by physicians approaching cancer pain patients. In light of the increased survival of cancer patients due to advances in therapy, deprescription should be considered as a part of the opioid prescribing regime, from therapy initiation, dose titration, and changing or adding drugs, to switching or ceasing. In clinical practice, opioid tapering after pain remission could be challenging due to withdrawal symptoms' onset. Animal models and observations in patients with opioid addiction suggested that somatic and motivational symptoms accompanying opioid withdrawal are secondary to the activation of stress-related process (mainly cortisol and catecholamines mediated). In this narrative review, we highlight how the lack of validated guidelines and tools for cancer patients can lead to a lower diagnostic awareness of opioid-related disorders, increasing the risk of developing withdrawal symptoms. We also described an experience-based approach to opioid withdrawal, starting from a case-report of a symptomatic patient with a history of metastatic pheochromocytoma-paraganglioma.

Acute stress modulates noradrenergic signaling in the ventral tegmental area-amygdalar circuit

Noradrenergic neurotransmission is a critical mediator of stress responses. In turn, exposure to stress induces noradrenergic system adaptations, some of which are implicated in the etiology of stress-related disorders. Adrenergic receptors (ARs) in the ventral tegmental area (VTA) have been demonstrated to regulate phasic dopamine (DA) release in the forebrain, necessary for behavioral responses to conditional cues. However, the impact of stress on noradrenergic modulation of the VTA has not been previously explored. We demonstrate that ARs in the VTA regulate dopaminergic activity in the VTA-BLA (basolateral amygdala) circuit, a key system for processing stress-related stimuli; and that such control is altered by acute stress. We utilized fast-scan cyclic voltammetry to assess the effects of intra-VTA microinfusion of α₁ -AR and α₂ -AR antagonists (terazosin and RX-821002, respectively), on electrically evoked phasic DA release in the BLA in stress-naïve and stressed (unavoidable electric shocks - UES) anesthetized male Sprague-Dawley rats. In addition, we used western blotting to explore UES-induced alterations in AR protein level in the VTA. Intra-VTA terazosin or RX-821002 dose-dependently attenuated DA release in the BLA. Interestingly, UES decreased the effects of intra-VTA α₂ -AR blockade on DA release (24 h but not 7 days after stress), while the effects of terazosin were unchanged. Despite changes in α₂ -AR physiological function in the VTA, UES did not alter α₂ -AR protein levels in either intracellular or membrane fractions. These findings demonstrate that NA-ergic modulation of the VTA-BLA circuit undergoes significant alterations in response to acute stress, with α₂ -AR signaling indicated as a key target.

Interactive Effects of µ-Opioid and Adrenergic-α 2 Receptor Agonists in Rats: Pharmacological Investigation of the Primary Kratom Alkaloid Mitragynine and Its Metabolite 7-Hydroxymitragynine

The primary kratom alkaloid mitragynine is proposed to act through multiple mechanisms, including actions at µ-opioid receptors (MORs) and adrenergic-α 2 receptors (Aα 2Rs), as well as conversion in vivo to a MOR agonist metabolite (i.e., 7-hydroxymitragynine). Aα 2R and MOR agonists can produce antinociceptive synergism. Here, contributions of both receptors to produce mitragynine-related effects were assessed by measuring receptor binding in cell membranes and, in rats, pharmacological behavioral effect antagonism studies. Mitragynine displayed binding affinity at both receptors, whereas 7-hydroxymitragynine only displayed MOR binding affinity. Compounds were tested for their capacity to decrease food-maintained responding and rectal temperature and to produce antinociception in a hotplate test. Prototypical MOR agonists and 7-hydroxymitragynine, but not mitragynine, produced antinociception. MOR agonist and 7-hydroxymitragynine rate-deceasing and antinociceptive effects were antagonized by the opioid antagonist naltrexone but not by the Aα 2R antagonist yohimbine. Hypothermia only resulted from reference Aα 2R agonists. The rate-deceasing and hypothermic effects of reference Aα 2R agonists were antagonized by yohimbine but not naltrexone. Neither naltrexone nor yohimbine antagonized the rate-decreasing effects of mitragynine. Mitragynine and 7-hydroxymitragynine increased the potency of the antinociceptive effects of Aα 2R but not MOR reference agonists. Only mitragynine produced hypothermic effects. Isobolographic analyses for the rate-decreasing effects of the reference Aα 2R and MOR agonists were also conducted. These results suggest mitragynine and 7-hydroxymitragynine may produce antinociceptive synergism with Aα 2R and MOR agonists. When combined with Aα 2R agonists, mitragynine could also produce hypothermic synergism. SIGNIFICANCE STATEMENT: Mitragynine is proposed to target the µ-opioid receptor (MOR) and adrenergic-α2 receptor (Aα2R) and to produce behavioral effects through conversion to its MOR agonist metabolite 7-hydroxymitragynine. Isobolographic analyses indicated supra-additivity in some dose ratio combinations. This study suggests mitragynine and 7-hydroxymitragynine may produce antinociceptive synergism with Aα2R and MOR agonists. When combined with Aα2R agonists, mitragynine could also produce hypothermic synergism.

CDC Clinical Practice Guideline for Prescribing Opioids for Pain - United States, 2022

This guideline provides recommendations for clinicians providing pain care, including those prescribing opioids, for outpatients aged ≥18 years. It updates the CDC Guideline for Prescribing Opioids for Chronic Pain - United States, 2016 (MMWR Recomm Rep 2016;65[No. RR-1]:1-49) and includes recommendations for managing acute (duration of <1 month), subacute (duration of 1-3 months), and chronic (duration of >3 months) pain. The recommendations do not apply to pain related to sickle cell disease or cancer or to patients receiving palliative or end-of-life care. The guideline addresses the following four areas: 1) determining whether or not to initiate opioids for pain, 2) selecting opioids and determining opioid dosages, 3) deciding duration of initial opioid prescription and conducting follow-up, and 4) assessing risk and addressing potential harms of opioid use. CDC developed the guideline using the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) framework. Recommendations are based on systematic reviews of the scientific evidence and reflect considerations of benefits and harms, patient and clinician values and preferences, and resource allocation. CDC obtained input from the Board of Scientific Counselors of the National Center for Injury Prevention and Control (a federally chartered advisory committee), the public, and peer reviewers. CDC recommends that persons with pain receive appropriate pain treatment, with careful consideration of the benefits and risks of all treatment options in the context of the patient's circumstances. Recommendations should not be applied as inflexible standards of care across patient populations. This clinical practice guideline is intended to improve communication between clinicians and patients about the benefits and risks of pain treatments, including opioid therapy; improve the effectiveness and safety of pain treatment; mitigate pain; improve function and quality of life for patients with pain; and reduce risks associated with opioid pain therapy, including opioid use disorder, overdose, and death.

Alpha-2A but not 2B/C noradrenergic receptors in ventral tegmental area regulate phasic dopamine release in nucleus accumbens core

Adrenergic receptors (AR) in the ventral tegmental area (VTA) modulate local neuronal activity and, as a consequence, dopamine (DA) release in the mesolimbic forebrain. Such modulation has functional significance: intra-VTA blockade of α₁-AR attenuates behavioral responses to salient environmental stimuli in rat models of drug seeking and conditioned fear as well as phasic DA release in the nucleus accumbens (NAc). In contrast, α₂-AR in the VTA has been suggested to act primarily as autoreceptors, limiting local noradrenergic input. The regulation of noradrenaline efflux by α₂-AR could be of clinical interest, as α₂-AR agonists are proposed as promising pharmacological tools in the treatment of PTSD and substance use disorder. Thus, the aim of our study was to determine the subtype-specificity of α₂-ARs in the VTA capable of modulating phasic DA release. We used fast scan cyclic voltammetry (FSCV) in anaesthetized male rats to measure DA release in the NAc after combined electrical stimulation and infusion of selected α₂-AR antagonists into the VTA. Intra-VTA microinfusion of idazoxan - a non-subtype-specific α₂-AR antagonist, as well as BRL-44408 - a selective α_2A-AR antagonist, attenuated electrically-evoked DA in the NAc. In contrast, local administration of JP-1302 or imiloxan (α_2B- and α_2C-AR antagonists, respectively) had no effect. The effect of BRL-44408 on DA release was attenuated by intra-VTA DA D₂ antagonist (raclopride) pre-administration. Finally, we confirmed the presence of α_2A-AR protein in the VTA using western blotting. In conclusion, these data specify α_2A-, but not α_2B- or α_2C-AR as the receptor subtype controlling NA release in the VTA.

Managing Opioid Withdrawal in an Outpatient Setting With Lofexidine or Clonidine

Background

There is a need for improved strategies for managing abrupt opioid withdrawal when transitioning patients with opioid use disorder to comprehensive longitudinal care strategies such as naltrexone maintenance treatment. In addition, alpha-2 adrenergic agonists are used to ameliorate withdrawal symptoms, but current data characterizing real-world treatment are lacking.

Methods

A retrospective chart review was conducted in outpatients undergoing abrupt opioid withdrawal managed with lofexidine (0.18 mg, 1-4 tablets 4x daily for 7 days, pro re nata [PRN or as needed]) or clonidine (0.2 mg, 1 tablet 3x daily for 10 days, PRN). Withdrawal outcomes were characterized at 30 days of follow-up. Binomial logistic regression was used to assess a potential association of the two treatments with different likelihoods of opioid cessation success in this real-world outpatient practice.

Results

In cases treated with lofexidine (n=166) and clonidine (n=432), respectively, 40% and 10% were opioid-free, 6% and 2% continued long-term buprenorphine or methadone, 17% and 36% relapsed, and 37% and 52% were lost to follow-up at 30 days post-withdrawal. Among patients returning for follow-up care, 63% of patients treated with lofexidine and 21% treated with clonidine were opioid-free. Lofexidine was associated with a higher likelihood of opioid cessation success relative to clonidine (OR=6.47; Wald Chi-square=53.79, p<0.001).

Conclusion

Among outpatients returning for follow-up care, nearly two-thirds of those managed with lofexidine reached opioid-free status at 30 days post-withdrawal, which was a higher likelihood than those managed with clonidine, thus allowing their transition to comprehensive care, including naltrexone.

Using Named Entity Recognition to Identify Substances Used in the Self-medication of Opioid Withdrawal: Natural Language Processing Study of Reddit Data

BACKGROUND

The cessation of opioid use can cause withdrawal symptoms. People often continue opioid misuse to avoid these symptoms. Many people who use opioids self-treat withdrawal symptoms with a range of substances. Little is known about the substances that people use or their effects.

OBJECTIVE

The aim of this study is to validate a methodology for identifying the substances used to treat symptoms of opioid withdrawal by a community of people who use opioids on the social media site Reddit.

METHODS

We developed a named entity recognition model to extract substances and effects from nearly 4 million comments from the r/opiates and r/OpiatesRecovery subreddits. To identify effects that are symptoms of opioid withdrawal and substances that are potential remedies for these symptoms, we deduplicated substances and effects by using clustering and manual review, then built a network of substance and effect co-occurrence. For each of the 16 effects identified as symptoms of opioid withdrawal in the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition, we identified the 10 most strongly associated substances. We classified these pairs as follows: substance is a Food and Drug Administration-approved or commonly used treatment for the symptom, substance is not often used to treat the symptom but could be potentially useful given its pharmacological profile, substance is a home or natural remedy for the symptom, substance can cause the symptom, or other or unclear. We developed the Withdrawal Remedy Explorer application to facilitate the further exploration of the data.

RESULTS

Our named entity recognition model achieved F1 scores of 92.1 (substances) and 81.7 (effects) on hold-out data. We identified 458 unique substances and 235 unique effects. Of the 130 potential remedies strongly associated with withdrawal symptoms, 54 (41.5%) were Food and Drug Administration-approved or commonly used treatments for the symptom, 17 (13.1%) were not often used to treat the symptom but could be potentially useful given their pharmacological profile, 13 (10%) were natural or home remedies, 7 (5.4%) were causes of the symptom, and 39 (30%) were other or unclear. We identified both potentially promising remedies (eg, gabapentin for body aches) and potentially common but harmful remedies (eg, antihistamines for restless leg syndrome).

CONCLUSIONS

Many of the withdrawal remedies discussed by Reddit users are either clinically proven or potentially useful. These results suggest that this methodology is a valid way to study the self-treatment behavior of a web-based community of people who use opioids. Our Withdrawal Remedy Explorer application provides a platform for using these data for pharmacovigilance, the identification of new treatments, and the better understanding of the needs of people undergoing opioid withdrawal. Furthermore, this approach could be applied to many other disease states for which people self-manage their symptoms and discuss their experiences on the web.

Use of continuous infusion of clonidine for sedation in critically ill infants and children

BACKGROUND

Adequate sedation and analgesia are required for critically ill children in order to minimize discomfort, reduce anxiety, and facilitate care. This is commonly achieved through a combination of opioids and benzodiazepines. Prolonged use of these agents is associated with tolerance and withdrawal. Clonidine as an adjunctive sedative agent may reduce sedation-related adverse events.

OBJECTIVE

Our first aim was to describe the indication for clonidine administration and its secondary effects in a mixed cohort of critically ill children. Our secondary aim was to measure the consumption of sedatives during two study periods: before and after the use of clonidine in our pediatric intensive care unit (PICU).

METHODS

This was a single-center study conducted in a tertiary PICU and encompassed retrospective chart review of patients who received clonidine between November 2013 and April 2015. We collected data on clonidine dosage, duration of administration, indication for the prescription, and potential side effects. We analyzed the total consumption of sedatives over 18 months, before and after the introduction of clonidine in our sedation protocol.

RESULTS

A total of patients received clonidine, with a mean age of 2.2 ± 2.8 years. The primary reason for intensive care admission was respiratory failure (48%). The main indication for clonidine administration was increasing requirement for morphine and midazolam (60%). The mean duration of clonidine infusion was 9 ± 7.3 days. Bradycardia and hypotension occurred in five patients (11.6%) and nine patients (21%), respectively. These side effects did not result in any major intervention. Younger age was a risk factor for clonidine-associated bradycardia. We observed a significant decrease in morphine and midazolam consumption with clonidine as a comedication. Compared with the pre-study period, consumption decreased by 19.7% for morphine and by 59% for midazolam (calculated as milligram/admission).

CONCLUSION

Continuous infusion of clonidine in critically ill children is safe and effective. Clonidine is a sedative-sparing agent and this can help reduce complications associated with prolonged use of opioids and benzodiazepines.

Beneficial Extracardiac Effects of Cardiovascular Medications

Cardiovascular diseases are the most common cause of death worldwide, with cardiovascular medications being amongst the most common medications prescribed. These medications have diverse effects on the heart, vascular system, as well as other tissues and organ systems. The extra cardiovascular effects have been found to be of use in the treatment of non-cardiovascular diseases and pathologies. Minoxidil is used to manage systemic hypertension with its well-known side effect of hirsutism used to treat alopecia and baldness. Sildenafil was originally investigated as a treatment option for systemic hypertension; however, its side effect of penile erection led to it being widely used for erectile dysfunction. Alpha-1 blockers such as terazosin are indicated to treat systemic hypertension but are more commonly used for benign prostatic hyperplasia and post-traumatic stress disorder. Beta blockers are the mainstay treatment for congestive heart failure and systemic hypertension but have been found useful to help in patients with intention tremors as well as prophylaxis of migraines. Similarly, calcium channel blockers are indicated in medical expulsion therapy for ureteric calculi in addition to their cardiovascular indications. Thiazides are commonly used for treating systemic hypertension and as diuretics. Thiazides can cause hypocalciuria and hypercalcemia. This side effect has led to thiazides being used to treat idiopathic hypercalciuria and associated nephrolithiasis. Spironolactone is commonly utilized in treating heart failure and as a diuretic for edema. It's well described anti-androgen side effects have been used for acne vulgaris and hirsutism in polycystic ovarian syndrome. This review article discusses how the various extracardiovascular effects of commonly used cardiovascular medications are put to use in managing non-cardiovascular conditions.

How to Manage Withdrawal of Sedation and Analgesia in Mechanically Ventilated COVID-19 Patients?

COVID-19 patients suffering from severe acute respiratory distress syndrome (ARDS) require mechanical ventilation (MV) for respiratory failure. To achieve these ventilatory goals, it has been observed that COVID-19 patients in particular require high regimens and prolonged use of sedatives, analgesics and neuromuscular blocking agents (NMBA). Withdrawal from analgo-sedation may induce a "drug withdrawal syndrome" (DWS), i.e., clinical symptoms of anxiety, tremor, agitation, hallucinations and vomiting, as a result of adrenergic activation and hyperalgesia. We describe the epidemiology, mechanisms leading to this syndrome and our strategies to prevent and treat it.

Problematic Opioid Use Among Older Adults: Epidemiology, Adverse Outcomes and Treatment Considerations

With the aging population, an increasing number of older adults (> 65 years) will be affected by problematic opioid use and opioid use disorder (OUD), with both illicit and prescription opioids. Problematic opioid use is defined as the use of opioids resulting in social, medical or psychological consequences, whereas OUD is a form of problematic use that meets diagnostic criteria as defined by the Diagnostic and Statistical Manual of Mental Disorders, 5th Edition. Problematic use of opioids by older adults is associated with a number of pertinent adverse effects, including sedation, cognitive impairment, falls, fractures and constipation. Risk factors for problematic opioid use in this population include pain, comorbid medical illnesses, concurrent alcohol use disorder and depression. Treatment of OUD consists of acute detoxification and maintenance therapy. At this time, there have been no randomized controlled trials examining the effectiveness of pharmacological interventions for OUD in this population, with recommendations based on data from younger adults. Despite this, opioid agonist therapy (OAT) is recommended for both stages of treatment in older adults with OUD. Buprenorphine is recommended as a first line agent over methadone in the older adult population, due to a more favourable safety profile and relative accessibility. Use of methadone in this population is complicated by risk of QT interval prolongation and respiratory depression. Available observational data suggests that older adults respond well to OAT and age should not be a barrier to treatment. Further research is required to inform treatment decisions in this population.

Sex Differences in Behavioral and Brainstem Transcriptomic Neuroadaptations following Neonatal Opioid Exposure in Outbred Mice

The opioid epidemic led to an increase in the number of neonatal opioid withdrawal syndrome (NOWS) cases in infants born to opioid-dependent mothers. Hallmark features of NOWS include weight loss, severe irritability, respiratory problems, and sleep fragmentation. Mouse models provide an opportunity to identify brain mechanisms that contribute to NOWS. Neonatal outbred Swiss Webster Cartworth Farms White (CFW) mice were administered morphine (15 mg/kg, s.c.) twice daily from postnatal day 1 (P1) to P14, an approximation of the third trimester of human gestation. Female and male mice underwent behavioral testing on P7 and P14 to determine the impact of opioid exposure on anxiety and pain sensitivity. Ultrasonic vocalizations (USVs) and daily body weights were also recorded. Brainstems containing pons and medulla were collected during morphine withdrawal on P14 for RNA sequencing. Morphine induced weight loss from P2 to P14, which persisted during adolescence (P21) and adulthood (P50). USVs markedly increased at P7 in females, emerging earlier than males. On P7 and P14, both morphine-exposed female and male mice displayed hyperalgesia on the hot plate and tail-flick assays, with females showing greater hyperalgesia than males. Morphine-exposed mice exhibited increased anxiety-like behavior in the open-field arena on P21. Transcriptome analysis of the brainstem, an area implicated in opioid withdrawal and NOWS, identified pathways enriched for noradrenergic signaling in females and males. We also found sex-specific pathways related to mitochondrial function and neurodevelopment in females and circadian entrainment in males. Sex-specific transcriptomic neuroadaptations implicate unique neurobiological mechanisms underlying NOWS-like behaviors.

Guidelines for the assessment and management of addiction in the hospitalized patient with opioid use disorder: a twenty-first century update

While there have been many articles published on managing the medical sequelae of opioid use disorder in specific patient populations or settings, there is a dearth of literature on assessing and managing opioid use disorder in the acute hospital setting. In 1975, Fultz and Senay published proposed guidelines on the management of what they called the "hospitalized narcotic addict" Fultz and Senay (Ann Intern Med 82(6):815-818, 1975). Since then, many new developments in the treatment of opioid use disorder have occurred. In our experience, services in the acute inpatient hospital turn to psychiatric consultation teams for recommendations on how to manage these complicated and, sometimes, difficult patients. This article serves to provide the internal medicine physician a foundation of understanding how to address the main issues in hospitalized patients with opioid use disorder on a general medical or surgical floor.

Opioid toxicity due to CNS depressant polypharmacy: A case report

The interaction between methadone and central nervous system depressants can cause serious adverse effects, including profound sedation, respiratory depression, coma, and death. This poses a challenge in the treatment of patients with concurrent psychiatric and substance use disorders as the combined use is often unavoidable. We report a case of a patient with opioid use disorder, mood disorder unspecified, chronic pain, and chronic obstructive pulmonary disease who experienced 2 serious episodes of CNS and respiratory depression due to polypharmacy-induced opioid toxicity. Careful consideration of pharmacokinetics, pharmacodynamics, and patient-specific factors was imperative to identify the suspected contributing medications: methadone, lorazepam, divalproex, gabapentin, and cyclobenzaprine. Cognitive and system factors that contributed to these adverse events and strategies to mitigate risk of recurrence were also identified.

Neurochemical mechanisms and neurocircuitry underlying the contribution of stress to cocaine seeking

In individuals with substance use disorders, stress is a critical determinant of relapse susceptibility. In some cases, stressors directly trigger cocaine use. In others, stressors interact with other stimuli to promote drug seeking, thereby setting the stage for relapse. Here, we review the mechanisms and neurocircuitry that mediate stress-triggered and stress-potentiated cocaine seeking. Stressors trigger cocaine seeking by activating noradrenergic projections originating in the lateral tegmentum that innervate the bed nucleus of the stria terminalis to produce beta adrenergic receptor-dependent regulation of neurons that release corticotropin releasing factor (CRF) into the ventral tegmental area (VTA). CRF promotes the activation of VTA dopamine neurons that innervate the prelimbic prefrontal cortex resulting in D1 receptor-dependent excitation of a pathway to the nucleus accumbens core that mediates cocaine seeking. The stage-setting effects of stress require glucocorticoids, which exert rapid non-canonical effects at several sites within the mesocorticolimbic system. In the nucleus accumbens, corticosterone attenuates dopamine clearance via the organic cation transporter 3 to promote dopamine signaling. In the prelimbic cortex, corticosterone mobilizes the endocannabinoid, 2-arachidonoylglycerol (2-AG), which produces CB1 receptor-dependent reductions in inhibitory transmission, thereby increasing excitability of neurons which comprise output pathways responsible for cocaine seeking. Factors that influence the role of stress in cocaine seeking, including prior history of drug use, biological sex, chronic stress/co-morbid stress-related disorders, adolescence, social variables, and genetics are discussed. Better understanding when and how stress contributes to drug seeking should guide the development of more effective interventions, particularly for those whose drug use is stress related.

Feasibility and Preliminary Efficacy of Isradipine During Outpatient Buprenorphine Stabilization and Detoxification: A Pilot Randomized, Placebo-Controlled Trial

Background:

Given the immense burden of the widespread use of opioids around the world, exploring treatments that improve drug use outcomes, and craving and withdrawal measures in individuals with opioid use disorder is crucial. This pilot study examined the feasibility and preliminary efficacy of the L-type calcium-channel blocker isradipine (ISR) to improve drug use outcomes, and craving and withdrawal measures during buprenorphine (BUP)/ISR stabilization and subsequent taper in opioid-dependent individuals.

Methods:

Participants were stabilized on BUP sublingual tablets within the first 2 days of week 1, were then randomized and inducted on either ISR or placebo, gradually increasing the dose over the next 2 weeks, followed by a 10-day BUP taper during weeks 5-6, and ISR/placebo taper during weeks 7 to 8. Assessments included thrice-weekly measures of craving and withdrawal, as well as vital signs and urine drug screens. Medication compliance was assessed by monitoring number of missed clinic visit days.

Results:

Baseline characteristics of participants (n = 25; 60% male, 96% Caucasian, 48% employed, mean age 32.8 years) did not differ significantly between treatment groups (isradipine, n = 11; placebo, n = 14). During the stabilization phase (n = 19), ISR participants had significantly lower rates of illicit opioid-positive urines (treatment × visit: t = -2.16, P = 0.03), as well as reduction in craving intensity (t = –2.50, P = 0.01), frequency (t = –3.43, P < 0.01) and duration (t = –2.51, P = 0.01). ISR was well tolerated with mild adverse effects.

Conclusions:

This study was likely underpowered due to being a pilot trial. Although preliminary results suggest ISR may improve BUP-assisted treatment outcomes, concerns about high number of exclusions (n = 11 during taper phase) based on cardiovascular measures as well as ISR-induced changes in vital signs with the immediate release formulation may limit the feasibility of this approach.

Trial Registration:

Clinicaltrials.gov identifier NCT01895270. Registered 10 July 2013, https://clinicaltrials.gov/ct2/show/NCT01895270?id=NCT01895270&draw=2&rank=1

Neurocovid: Pharmacological Recommendations for Delirium Associated With COVID-19

BACKGROUND

The pandemic of coronavirus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has emerged as one of the biggest health threats of our generation. A significant portion of patients are presenting with delirium and neuropsychiatric sequelae of the disease. Unique examination findings and responses to treatment have been identified.

OBJECTIVE

In this article, we seek to provide pharmacologic and treatment recommendations specific to delirium in patients with COVID-19.

METHODS

We performed a literature search reviewing the neuropsychiatric complications and treatments in prior coronavirus epidemics including Middle Eastern respiratory syndrome and severe acute respiratory syndrome coronaviruses, as well as the emerging literature regarding COVID-19. We also convened a work group of consultation-liaison psychiatrists actively managing patients with COVID-19 in our hospital. Finally, we synthesized these findings to provide preliminary pharmacologic recommendations for treating delirium in these patients.

RESULTS

Delirium is frequently found in patients who test positive for COVID-19, even in the absence of respiratory symptoms. There appears to be a higher rate of agitation, myoclonus, abulia, and alogia. No data are currently available on the treatment of delirium in patients with COVID-19. Extrapolating from general delirium treatment, Middle Eastern respiratory syndrome/severe acute respiratory syndrome case reports, and our experience, preliminary recommendations for pharmacologic management have been assembled.

CONCLUSIONS

COVID-19 is associated with neuropsychiatric symptoms. Low-potency neuroleptics and alpha-2 adrenergic agents may be especially useful in this setting. Further research into the pathophysiology of COVID-19 will be key in developing more targeted treatment guidelines.

A Comprehensive Update of Lofexidine for the Management of Opioid Withdrawal Symptoms

PURPOSE OF REVIEW

This is a comprehensive review of the literature regarding the use of Lofexidine for opiate withdrawal symptoms. It covers the background and necessity of withdrawal programs and the management of withdrawal symptoms and then covers the existing evidence of the use of Lofexidine for this purpose.

RECENT FINDINGS

Opiate abuse leads to significant pain and suffering. However, withdrawal is difficult and often accompanied by withdrawal symptoms and renewed cravings. These symptoms are driven mostly by signaling in the locus coeruleus and the mesolimbic system and a rebound increase in noradrenaline, producing symptoms such as anxiety, gastrointestinal upset, and tension. Lofexidine, an alpha-2 agonist, can be used to manage acute withdrawal symptoms before starting maintenance treatment with either methadone or buprenorphine. Lofexidine, if FDA approved for management of withdrawal symptoms and has been proved to be both effective and safe.

SUMMARY

Opiate addiction is increasing and plaguing the western world and specifically the U.S. It takes a large toll on both a personal and societal level and carries a high cost. Withdrawal is difficult, both related to withdrawal symptoms and renewed cravings. Lofexidine has been shown to be effective in reducing the former and could potentially aid in recovery and withdrawal.

Safety and Efficacy of Lofexidine for Medically Managed Opioid Withdrawal: A Randomized Controlled Clinical Trial

Supplemental Digital Content is available in the text

Objectives:

To investigate the safety and efficacy of lofexidine for treating opioid withdrawal syndrome (OWS) and facilitating completion of opioid withdrawal.

Methods:

A multicenter, double-blind, placebo-controlled study was conducted at 18 US centers from June 2013 to December 2014. Participants (n = 603) aged ≥18 years, dependent on short-acting opioids, and seeking withdrawal treatment, randomized 3:3:2 to receive lofexidine 2.88 mg/d (n = 222), lofexidine 2.16 mg/d (n = 230), or placebo (n = 151) for 7 days. Primary outcome was the Short Opiate Withdrawal Scale of Gossop (SOWS-Gossop) scores rating withdrawal symptoms over days 1 to 7.

Results:

Participants were of mean age, 35 years; 71% male. Pairwise differences in overall SOWS-Gossop log-transformed least squares means were statistically significant for lofexidine 2.16 mg (difference, −0.21; 95% CI, −0.37 to −0.04; P = 0.02) and 2.88 mg (−0.26; 95% CI, −0.44 to −0.09; P = 0.003) compared with placebo. Fewer than half of participants in both groups completed the study. Completion rates for lofexidine 2.16 mg (41.5%; odds ratio [OR], 1.85; P = 0.007) and 2.88 mg (39.6%; OR, 1.71; P = 0.02) were significantly better compared with placebo (27.8%). Overall adverse event (AE) rates were similar across groups. Common AEs for lofexidine included orthostatic hypotension, hypotension, and bradycardia, but resulted in few study discontinuations.

Conclusions:

Lofexidine 2.16 mg and 2.88 mg significantly reduced symptoms of OWS versus placebo, and increased absolute rates of completing the 7-day study by 14% and 12%, respectively (a relative increase of 85% and 71%). Data suggest that lofexidine is a generally safe and effective nonopioid treatment for opioid withdrawal. Lofexidine could serve as a withdrawal treatment option when a nonopioid agent is preferred or required, when agonist-assisted withdrawal is unavailable, when agonist discontinuation caused OWS, and during induction into maintenance treatment with opioid agonists or antagonists.

Trial Registration:

ClinicalTrials.gov identifier: NCT01863186.

New directions in the treatment of opioid withdrawal

The treatment of opioid withdrawal is an important area of clinical concern when treating patients with chronic, non-cancer pain, patients with active opioid use disorder, and patients receiving medication for opioid use disorder. Current standards of care for medically supervised withdrawal include treatment with μ-opioid receptor agonists, (eg, methadone), partial agonists (eg, buprenorphine), and α2-adrenergic receptor agonists (eg, clonidine and lofexidine). Newer agents likewise exploit these pharmacological mechanisms, including tramadol (μ-opioid receptor agonism) and tizanidine (α2 agonism). Areas for future research include managing withdrawal in the context of stabilising patients with opioid use disorder to extended-release naltrexone, transitioning patients with opioid use disorder from methadone to buprenorphine, and tapering opioids in patients with chronic, non-cancer pain.

Evaluation of selective outcome reporting and trial registration practices among addiction clinical trials

BACKGROUND AND AIMS

Selective outcome reporting occurs when trialists pre-specify primary and secondary outcomes during trial planning but alter the definitions in the published report. Here, we investigate selective outcome reporting in published addiction randomized controlled trials (RCTs) and evaluate whether particular funding sources are associated with an increased likelihood of selective outcome reporting.

DESIGN

We conducted a cross-sectional study of published addiction clinical trials. A PubMed search was performed to identify RCTs in addiction journals from 2013 to 2017. Included studies used a randomized design to address one of the following topics: (1) drug, alcohol and tobacco addiction prevention, (2) stabilization following excessive use of a substance, (3) relapse prevention or (4) recovery maintenance.

SETTING

Single-center, medical research institution.

PARTICIPANTS

Our sample included 162 RCTs that were prospectively registered with a clearly defined primary outcome.

MEASUREMENT

We extracted the following items from addiction RCTs: journal, funding source, trial registry number (if included), sample size, dates of subject enrollment, whether primary and secondary outcomes were denoted, all published outcomes, P-value for all outcomes and whether authors mentioned any deviations from the trial protocol as it related to RCT outcomes.

FINDINGS

In total, 47 of 162 RCTs (29.0%) had at least one major discrepancy between the trial registry and published RCT. Overall, these 47 RCTs included 54 major discrepancies. The most common major discrepancy was demotion of a primary registered outcome (19/54, 35.2%). The majority of RCTs (132/162, 81.5%) were funded from public sources. Additionally, 166 RCTs were excluded from our sample because registration could not be confirmed.

CONCLUSIONS

There is evidence suggestive of selective outcome reporting in addiction randomized controlled trials (RCTs). The most common major discrepancies pertained to the primary outcome.

Opioid Management: Initiating, Monitoring, and Tapering

Numerous guidelines targeting safe use of opioids for chronic pain have been published but substantial challenges persist in clinical application of best practice recommendations. This article describes a pragmatic approach to clinical care of adults with chronic pain receiving long-term opioid therapy. Three components of care are emphasized: (1) medical and mental health assessment before initiating opioid therapy, (2) clinical surveillance during the course of long-term opioid therapy, and (3) clinical considerations and strategies governing opioid tapering. A pressing need exists for ongoing research to further clarify the optimal role that long-term opioid therapy has in treatment of chronic pain.

Canadian Guidelines on Opioid Use Disorder Among Older Adults

BACKGROUND

In Canada, rates of hospital admission from opioid overdose are higher for older adults (≥ 65) than younger adults, and opioid use disorder (OUD) is a growing concern. In response, Health Canada commissioned the Canadian Coalition of Seniors' Mental Health to create guidelines for the prevention, screening, assessment, and treatment of OUD in older adults.

METHODS

A systematic review of English language literature from 2008-2018 regarding OUD in adults was conducted. Previously published guidelines were evaluated using AGREE II, and key guidelines updated using ADAPTE method, by drawing on current literature. Recommendations were created and assessed using the GRADE method.

RESULTS

Thirty-two recommendations were created. Prevention recommendations: it is key to prioritize non-pharmacological and non-opioid strategies to treat acute and chronic noncancer pain. Assessment recommendations: a comprehensive assessment is important to help discern contributions of other medical conditions. Treatment recommendations: buprenorphine is first line for both withdrawal management and maintenance therapy, while methadone, slow-release oral morphine, or naltrexone can be used as alternatives under certain circumstances; non-pharmacological treatments should be offered as an integrated part of care.

CONCLUSION

These guidelines provide practical and timely clinical recommendations on the prevention, assessment, and treatment of OUD in older adults within the Canadian context.

Dihydrocodeine for detoxification and maintenance treatment in individuals with opiate use disorders

BACKGROUND

Medical treatment and detoxification from opiate disorders includes oral administration of opioid agonists. Dihydrocodeine (DHC) substitution treatment is typically low threshold and therefore has the capacity to reach wider groups of opiate users. Decisions to prescribe DHC to patients with less severe opiate disorders centre on its perceived safety, reduced toxicity, shorter half-life and more rapid onset of action, and potential retention of patients. This review set out to investigate the effects of DHC in comparison to other pharmaceutical opioids and placebos in the detoxification and substitution of individuals with opiate use disorders.

OBJECTIVES

To investigate the effectiveness of DHC in reducing illicit opiate use and other health-related outcomes among adults compared to other drugs or placebos used for detoxification or substitution therapy.

SEARCH METHODS

In February 2019 we searched Cochrane Drugs and Alcohol's Specialised Register, CENTRAL, PubMed, Embase and Web of Science. We also searched for ongoing and unpublished studies via ClinicalTrials.gov, the World Health Organization (WHO) International Clinical Trials Registry Platform (ICTRP) and Trialsjournal.com. All searches included non-English language literature. We handsearched references of topic-related systematic reviews and the included studies.

SELECTION CRITERIA

We included randomised controlled trials that evaluated the effect of DHC for detoxification and maintenance substitution therapy for adolescent (aged 15 years and older) and adult illicit opiate users. The primary outcomes were abstinence from illicit opiate use following detoxification or maintenance therapy measured by self-report or urinalysis. The secondary outcomes were treatment retention and other health and behaviour outcomes.

DATA COLLECTION AND ANALYSIS

We followed the standard methodological procedures that are outlined by Cochrane. This includes the GRADE approach to appraise the quality of evidence.

MAIN RESULTS

We included three trials (in five articles) with 385 opiate-using participants that measured outcomes at different follow-up periods in this review. Two studies with 150 individuals compared DHC with buprenorphine for detoxification, and one study with 235 participants compared DHC to methadone for maintenance substitution therapy. We downgraded the quality of evidence mainly due to risk of bias and imprecision. For the two studies that compared DHC to buprenorphine, we found low-quality evidence of no significant difference between DHC and buprenorphine for detoxification at six-month follow-up (risk ratio (RR) 0.59, 95% confidence interval (CI) 0.25 to 1.39; P = 0.23) in the meta-analysis for the primary outcome of abstinence from illicit opiates. Similarly, low-quality evidence indicated no difference for treatment retention (RR 1.29, 95% CI 0.99 to 1.68; P = 0.06). In the single trial that compared DHC to methadone for maintenance substitution therapy, the evidence was also of low quality, and there may be no difference in effects between DHC and methadone for reported abstinence from illicit opiates (mean difference (MD) -0.01, 95% CI -0.31 to 0.29). For treatment retention at six months' follow-up in this single trial, the RR calculated with an intention-to-treat analysis also indicated that there may be no difference between DHC and methadone (RR 1.04, 95% CI 0.94 to 1.16). The studies that compared DHC to buprenorphine reported no serious adverse events, while the DHC versus methadone study reported one death due to methadone overdose.

AUTHORS' CONCLUSIONS

We found low-quality evidence that DHC may be no more effective than other commonly used pharmacological interventions in reducing illicit opiate use. It is therefore premature to make any conclusive statements about the effectiveness of DHC, and it is suggested that further high-quality studies are conducted, especially in low- to middle-income countries.

Effect of lofexidine on cardiac repolarization during treatment of opioid withdrawal

BACKGROUND

Lofexidine is a non-opioid treatment for opioid withdrawal syndrome. Its sympatholytic actions counteract the nor-adrenergic hyperactivity that occurs during abrupt opioid withdrawal.

METHODS

The effect of lofexidine 2.16 and 2.88 mg/day on QTcF (QT interval, heart-rate corrected, Fridericia formula) was studied as part of a large, double-blind, placebo-controlled trial (ClinicalTrials.gov identifier: NCT01863186). ECGs were time-matched to blood sampling for lofexidine concentration and were collected at prespecified timepoints over a 7-day inpatient period. Analyses included mean change-from-baseline QTcF and exposure-response modeling to predict QTcF at relevant lofexidine concentrations.

RESULTS

A total of 681 adult men and women received at least 1 dose of study drug; 566 qualified for inclusion in the concentration-QTcF analysis. Most subjects were withdrawing from heroin. During the first 24 h (Days 1-2) post-baseline, small increases in QTcF were observed in all groups: 4.7 ms for lofexidine 2.16 mg, 7.4 ms for lofexidine 2.88 mg and 1.4 ms for placebo. These increases were transient; by Day 4, when lofexidine levels had reached steady-state, QTcF increases were not present. By Day 7, QTcF was decreased from baseline in all groups. Exposure-response modeling predicted <10 ms increases in QTcF at lofexidine concentrations 3 times those obtained at maximal recommended dose.

CONCLUSIONS

Lofexidine was associated with small, transient QTcF increases. Decreases in QTcF that occurred with higher lofexidine concentrations argue for an indirect QTcF effect, potentially from changes in autonomic tone. Both opioid withdrawal and lofexidine's sympatholytic actions would be expected to alter sympathetic outflow over the 7-day withdrawal.

Non-Opioid Neurotransmitter Systems that Contribute to the Opioid Withdrawal Syndrome: A Review of Preclinical and Human Evidence

Opioid misuse and abuse is a major international public health issue. Opioid use disorder (OUD) is largely maintained by a desire to suppress aversive opioid withdrawal symptoms. Opioid withdrawal in patients seeking abstinence from illicit or prescribed opioids is often managed by provision of a μ-opioid agonist/partial agonist in combination with concomitant medications. Concomitant medications are administered based on their ability to treat specific symptoms rather than a mechanistic understanding of the opioid withdrawal syndrome; however, their use has not been statistically associated with improved treatment outcomes. Understanding the central and/or peripheral mechanisms that underlie individual withdrawal symptom expression in humans will help promote medication development for opioid withdrawal management. To support focused examination of mechanistically supported concomitant medications, this review summarizes evidence from preclinical (N = 68) and human (N = 30) studies that administered drugs acting on the dopamine, serotonin, cannabinoid, orexin/hypocretin, and glutamate systems and reported outcomes related to opioid withdrawal. These studies provide evidence that each of these systems contribute to opioid withdrawal severity. The Food and Drug Administration has approved medications acting on these respective systems for other indications and research in this area could support the repurposing of these medications to enhance opioid withdrawal treatment. These data support a focused examination of mechanistically informed concomitant medications to help reduce opioid withdrawal severity and enhance the continuum of care available for persons with OUD.

CYP2B6 Genotype-Dependent Inhibition of CYP1A2 and Induction of CYP2A6 by the Antiretroviral Drug Efavirenz in Healthy Volunteers

We investigated the effect of efavirenz on the activities of cytochrome P450 (CYP)1A2, CYP2A6, xanthine oxidase (XO), and N-acetyltransferase 2 (NAT2), using caffeine as a probe. A single 150 mg oral dose of caffeine was administered to healthy volunteers (n = 58) on two separate occasions; with a single 600 mg oral dose of efavirenz and after treatment with 600 mg/day efavirenz for 17 days. Caffeine and its metabolites in plasma and urine were quantified using liquid chromatography/tandem-mass spectrometry. DNA was genotyped for CYP2B6*4 (785A>G), CYP2B6*9 (516G>T), and CYP2B6*18 (983T>C) alleles using TaqMan assays. Relative to single-dose efavirenz treatment, multiple doses of efavirenz decreased CYP1A2 (by 38%) and increased CYP2A6 (by 85%) activities (P < 0.05); XO and NAT2 activities were unaffected. CYP2B6*6*6 genotype was associated with lower CYP1A2 activity following both single and multiple doses of efavirenz. No similar association was noted for CYP2A6 activity. This is the first report showing that efavirenz reduces hepatic CYP1A2 and suggesting chronic efavirenz exposure likely enhances the elimination of CYP2A6 substrates. This is also the first to report the extent of efavirenz-CYP1A2 interaction may be efavirenz exposure-dependent and CYP2B6 genotype-dependent.

The Neuroscience of Drug Reward and Addiction

Drug consumption is driven by a drug's pharmacological effects, which are experienced as rewarding, and is influenced by genetic, developmental, and psychosocial factors that mediate drug accessibility, norms, and social support systems or lack thereof. The reinforcing effects of drugs mostly depend on dopamine signaling in the nucleus accumbens, and chronic drug exposure triggers glutamatergic-mediated neuroadaptations in dopamine striato-thalamo-cortical (predominantly in prefrontal cortical regions including orbitofrontal cortex and anterior cingulate cortex) and limbic pathways (amygdala and hippocampus) that, in vulnerable individuals, can result in addiction. In parallel, changes in the extended amygdala result in negative emotional states that perpetuate drug taking as an attempt to temporarily alleviate them. Counterintuitively, in the addicted person, the actual drug consumption is associated with an attenuated dopamine increase in brain reward regions, which might contribute to drug-taking behavior to compensate for the difference between the magnitude of the expected reward triggered by the conditioning to drug cues and the actual experience of it. Combined, these effects result in an enhanced motivation to "seek the drug" (energized by dopamine increases triggered by drug cues) and an impaired prefrontal top-down self-regulation that favors compulsive drug-taking against the backdrop of negative emotionality and an enhanced interoceptive awareness of "drug hunger." Treatment interventions intended to reverse these neuroadaptations show promise as therapeutic approaches for addiction.

The Role of Lofexidine in Management of Opioid Withdrawal

Fear of withdrawal symptoms has been cited by survey respondents as the main reason that they continued to use opioids. Lofexidine is an α2-adrenergic agonist that decreases the sympathetic outflow that results in the characteristic symptoms of opioid withdrawal. A structural analog of clonidine, lofexidine has a higher affinity and specificity for the α2a receptors and does not reinforce opioid dependence. Withdrawal symptoms correlate approximately to the half-life of the opioid; patient factors such as age, duration of opioid exposure, physical status, and other considerations may influence the nature and duration of withdrawal symptoms. For patients with opioid use disorder and psychiatric comorbidities, withdrawal may be destabilizing and may exacerbate mental health status. Lofexidine has been shown in clinical trials to be safe and effective in helping to manage the symptoms of withdrawal and has been recommended in guidelines for this purpose. Adverse events associated with lofexidine include QT prolongation, hypotension, orthostasis, and bradycardia. The maximum course of treatment is 14 days, and doses should be titrated, with the recommended maximum dose to coincide with the most severe withdrawal symptoms (about 5-7 days after opioid discontinuation).

Use of Gabapentin in the Treatment of Substance Use and Psychiatric Disorders: A Systematic Review

Objective: Gabapentin (GBP) is an anticonvulsant medication that is also used to treat restless legs syndrome (RLS) and posttherapeutic neuralgia. GBP is commonly prescribed off-label for psychiatric disorders despite the lack of strong evidence. However, there is growing evidence that GBP may be effective and clinically beneficial in both psychiatric disorders and substance use disorders. This review aimed to perform a systematic analysis of peer-reviewed published literature on the efficacy of GBP in the treatment of psychiatric disorders and substance use disorders. Methods: This review was performed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. The PubMed and Ovid MEDLINE literature databases were screened and filtered by using specific search terms and inclusion/exclusion criteria. The full texts of selected studies were subsequently retrieved and reviewed. The search terms generated 2,604 results from the databases. After excluding all duplicates, 1,088 citations were left. Thereafter, we applied inclusion and exclusion criteria; a total of 54 papers were retained for detailed review. Results: This literature review concludes that GBP appears to be effective in the treatment of various forms of anxiety disorders. It shows some effectiveness in bipolar disorder as an adjunctive therapeutic agent, while the evidence for monotherapy is inconclusive. In substance use disorders, GBP is effective for acute alcohol withdrawal syndrome (AWS) with mild to moderate severity; it reduces cravings, improves the rate of abstinence, and delays return to heavy drinking. GBP may have some therapeutic potential in the treatment of opioid addiction and cannabis dependence, but there is limited evidence to support its use. No significant benefit of GBP has been conclusively observed in the treatment of OCD, PTSD, depression, or cocaine and amphetamine abuse. Conclusion: GBP appears to be effective in some forms of anxiety disorders such as preoperative anxiety, anxiety in breast cancer survivors, and social phobia. GBP has shown to be safe and effective in the treatment of alcohol dependence. However, the literature suggests that GBP is effective as an adjunctive medication rather than a monotherapy. More clinical trials with larger patient populations are needed to support gabapentin's off-label use in psychiatric disorders and substance use disorders. It is worth noting that numerous clinical studies that are discussed in this review are open-label trials, which are inherently less rigorously analyzed. Therefore, more extensive investigations are required to examine not only the efficacy of GBP, but also its safety and tolerance.

Guanfacine Augmentation of a Combined Intervention of Computerized Cognitive Remediation Therapy and Social Skills Training for Schizotypal Personality Disorder

OBJECTIVE

Impaired cognition is a hallmark of schizophrenia spectrum disorders, including schizotypal personality disorder, and it is the best predictor of functional outcome. Cognitive remediation therapy has demonstrated efficacy for improving cognition, augmenting other rehabilitation efforts in schizophrenia, and effecting gains in real-world functioning. Pharmacological augmentation of cognitive remediation has been attempted, but the effects of augmentation on combined therapies, such as cognitive remediation and social skills training, have not been studied.

METHODS

Twenty-eight participants with schizotypal personality disorder enrolled in an 8-week, randomized, double-blind, placebo-controlled trial of guanfacine plus cognitive remediation and social skills training (15 guanfacine, 13 placebo). Cognition was assessed with the MATRICS (Measurement and Treatment Research to Improve Cognition in Schizophrenia) Consensus Cognitive Battery (MCCB), social cognition with the Movie for the Assessment of Social Cognition (MASC), and functional capacity with the University of California San Diego Performance-Based Skills Assessment (UPSA).

RESULTS

A statistically significant pre- versus posttreatment effect was observed for MCCB speed of processing, verbal learning, and visual learning and UPSA total score. A significant time-by-medication (guanfacine, placebo) interaction was observed for MCCB reasoning and problem solving and UPSA total score; the time-by-treatment interaction approached significance for MASC hypomentalizing errors.

CONCLUSIONS

Both guanfacine and cognitive remediation plus social skills training were well tolerated, with no side effects or dropouts. Participants treated with cognitive remediation, social skills training, and guanfacine demonstrated statistically significant improvements in reasoning and problem solving, as well as in functional capacity and possibly social cognition, compared with those treated with cognitive remediation, social skills training, and placebo. Cognitive remediation plus social skills training may be an appropriate intervention for individuals with schizotypal personality disorder, and guanfacine appears to be a promising pharmaceutical augmentation to this psychosocial intervention.

Review article: Effective management of opioid withdrawal symptoms: A gateway to opioid dependence treatment

BACKGROUND AND OBJECTIVES

The opioid crisis has taken an immense toll in the United States. On average, five lives are lost to an opioid overdose every hour of the day; estimated costs associated with opioid misuse exceed $500 billion annually. Illicit opioid discontinuation is the first step in the treatment of opioid use disorder (OUD), and transition to an opioid agonist may initiate treatment. However, discontinuation to abstinence from either OUD directly or following agonist treatment results in severely distressing opioid withdrawal symptoms (OWS).

METHODS

This review evaluated studies on the etiology, burden, and management of OWS.

RESULTS

Noradrenergic hyperactivity generates many OWS. These OWS can cause patients to relapse during early opioid discontinuation. While agonist therapies are generally first-line for moderate or severe OUD and reduce OWS, prescribing restrictions can limit their availability.

DISCUSSION AND CONCLUSIONS

Non-opioid medications to treat OWS provides a gateway into long-term treatment with naltrexone or psychosocial therapies. For opioid dependent patients without OUD, non-opioid treatments like α-2 adrenergic agonists can facilitate opioid tapering.

SCIENTIFIC SIGNIFICANCE

For the millions who are physically dependent on opioids, new treatments for OWS can enhance recovery from OUD and prevent relapse. (© 2019 The Authors. The American Journal on Addictions Published by Wiley Periodicals, Inc.;XX:1-8).

Pharmacologic Treatment of Opioid Use Disorder: a Review of Pharmacotherapy, Adjuncts, and Toxicity

Opioid use disorder continues to be a significant source of morbidity and mortality in the USA and the world. Pharmacologic treatment with methadone and buprenorphine has been shown to be effective at retaining people in treatment programs, decreasing illicit opioid use, decreasing rates of hepatitis B, and reducing all cause and overdose mortality. Unfortunately, barriers exist in accessing these lifesaving medications: users wishing to start buprenorphine therapy require a waivered provider to prescribe the medication, while some states have no methadone clinics. As such, users looking to wean themselves from opioids or treat their opioid dependence will turn to alternative agents. These agents include using prescription medications, like clonidine or gabapentin, off-label, or over the counter drugs, like loperamide, in supratherapeutic doses. This review provides information on the pharmacology and the toxic effects of pharmacologic agents that are used to treat opioid use disorder. The xenobiotics reviewed in depth include buprenorphine, clonidine, kratom, loperamide, and methadone, with additional information provided on lofexidine, akuamma seeds, kava, and gabapentin.

Implementation of an Opioid Detoxification Management Pathway Reduces Emergency Department Length of Stay

OBJECTIVES

With the rise of opioid use in the United States, the increasing demand for treatment for opioid use disorders presents both a challenge and an opportunity to develop new care pathways for emergency department (ED) patients seeking opioid detoxification. We set out to improve the care of patients presenting to our ED seeking opioid detoxification by implementing a standardized management pathway and to measure the effects of this intervention.

METHODS

We conducted a before-after study of the effects of an opioid detoxification management pathway on ED length of stay (EDLOS), use of resources (social worker consultation, laboratory tests obtained), and return visits to the same ED within 30 days of discharge. All data were collected retrospectively by review of the electronic health record.

RESULTS

Ultimately, 107 patients presented to the ED that met criteria, 52 in the intervention period and 55 in the preintervention period. Median EDLOS in the intervention period was 152 (interquartile range [IQR] = 93-237) minutes compared to 312 (IQR = 187-468) minutes in the preintervention period (p < 0.001). Patients in the intervention period less frequently had a social work consultation (32.7% vs. 83.6%, p < 0.001) or had laboratory tests obtained (32.7% vs 74.5%, p < 0.001) and more frequently were prescribed a medication for withdrawal symptoms (57.7% vs. 29.1%, p = 0.003).

CONCLUSIONS

Implementation of an opioid detoxification management pathway reduced EDLOS, reduced utilization of resources, and increased the proportion of patients prescribed medications for symptom relief.

Negative experiences of pain and withdrawal create barriers to abscess care for people who inject heroin. A mixed methods analysis

BACKGROUND

Skin and soft tissue infections (SSTIs) are prevalent among people who inject heroin (PWIH). Delays in seeking health care lead to increased costs and potential mortality, yet the barriers to accessing care among PWIHs are poorly understood.

METHODS

We administered a quantitative survey (N = 145) and conducted qualitative interviews (N = 12) with PWIH seeking syringe exchange services in two U.S. cities.

RESULTS

66% of participants had experienced at least one SSTI. 38% reported waiting two weeks or more to seek care, and 57% reported leaving the hospital against medical advice. 54% reported undergoing a drainage procedure performed by a non-medical professional, and 32% reported taking antibiotics that were not prescribed to them. Two of the most common reasons for these behaviors were fear of withdrawal symptoms and inadequate pain control, and these reasons emerged as prominent themes in the qualitative findings. These issues are often predicated on previous negative experiences and exacerbated by stigma and an asymmetrical power dynamic with providers, resulting in perceived barriers to seeking and completing care for SSTIs.

CONCLUSIONS

For PWIH, unaddressed pain and withdrawal symptoms contribute to profoundly negative health care experiences, which then generate motivation for delaying care SSTI seeking and for discharge against medical advice. Health care providers and hospitals should develop policies to improve pain control, manage opioid withdrawal, minimize prejudice and stigma, and optimize communication with PWIH. These barriers should also be addressed by providing medical care in accessible and acceptable venues, such as safe injection facilities, street outreach, and other harm reduction venues.

Chronic Headache Due to Overuse of Analgesics and Anti-Migraine Agents

BACKGROUND

The frequent or regular use of analgesics and anti-migraine drugs can make headache more frequent and induce the transformation of episodic to chronic headache. Chronic headache due to medication overuse is defined as headache that is present on ≥ 15 days per month for at least three months in a patient who previously suffered from primary headaches, and who takes analgesics on ≥ 15 days per month or anti-migraine drugs (triptans or ergot alkaloids), opioid drugs, or combined analgesics on ≥ 10 days per month.

METHODS

This review is based on pertinent articles published up to December 2017 that were retrieved by a selective search in PubMed employing the terms "medication overuse AND headache" and "medication overuse headache."

RESULTS

The prevalence of medication overuse headache in the general population in Germany is 0.7% -1%. This disorder is more common in women and in persons suffering from comorbid mental disorders or other painful conditions. The treatment of medication overuse headache consists of three steps. Patient education and counseling are given with the goal of reducing the intake of medication for acute headache treatment. The ensuing headache prophylaxis is with topiramate, amitriptyline, or onabotulinum toxin A. If these treatment strategies fail, a drug holiday is recommended. This can be in the outpatient, day clinic, or inpatient setting, depending on the severity of the condition and its comorbidities.

CONCLUSION

Patients who frequently take acute medication to treat headache episodes must be identified early in order to avoid headache chronification and medication overuse headache. The suggested treatment algorithm is still in need of validation by randomized trials.

Rhynchophylline Downregulates Phosphorylated cAMP Response Element Binding Protein, Nuclear Receptor-related-1, and Brain-derived Neurotrophic Factor Expression in the Hippocampus of Ketamine-induced Conditioned Place Preference Rats

Background:

Addiction to ketamine is becoming a serious public health issues, for which there exists no effective treatment. Rhynchophylline (Rhy) is an alkaloid extracted from certain Uncaria species that is well known for both its potent anti-addictive and neuroprotective properties. Increasing evidence supports the contributions of cAMP response element binding protein (CREB), nuclear receptor-related-1 (Nurr1), and brain-derived neurotrophic factor (BDNF) in modulating neural and behavioral plasticity which was induced by addictive drugs.

Objective:

To investigate the effects of Rhy on the behavior and the levels of phosphorylated CREB (p-CREB), Nurr1, and BDNF in the hippocampus of ketamine-induced conditioned place preference (CPP) rats.

Materials and Methods:

CPP paradigm was used to establish the model of ketamine-dependent rats and to evaluate the effect of Rhy on ketamine dependence. The expressions of p-CREB, Nurr1, and BDNF were tested by Western blotting and immunohistochemistry.

Results:

We observed that Rhy can reverse the behavior preference induced by ketamine CPP training. At the same time, expression of p-CREB, Nurr1, and BDNF, which was significantly increased by ketamine, was restored in the Rhy -treated group.

Conclusion:

This study indicates that Rhy can reverse the reward effect induced by ketamine in rats and the mechanism can probably be related to regulate the hippocampal protein expression of p-CREB, Nurr1, and BDNF.

SUMMARY

P-CREB, Nurr1 and BDNF play an important role in the formation of ketamine-induced place preference in rats

Rhynchophylline reversed the expression of p-CREB, Nurr1 and BDNF which was activated by ketamine in the hippocampus

Rhynchophylline demonstrates the potential effect of mediates ketamine induced rewarding effect.

Abbreviations used: Rhy: Rhynchophylline; CREB: cAMP response element binding protein; Nurr1: Nuclear receptor-related-1; BDNF: Brain-derived neurotrophic factor; CPP: Conditioned place preference; NMDA: N-methyl-D-aspartic acid; METH: Methamphetamine; CNS: Central nervous system; PFA: Paraformaldehyde; GAPDH: Glyceraldehyde-3-phosphate dehydrogenase; LTP: long-term potentiation.