Serotonin syndrome

Diagnostic Approach to the Patient with Altered Mental Status

Acute encephalopathy is a common presenting symptom in the emergency room and complicates many hospital and intensive care unit admissions. The evaluation of patients with encephalopathy poses several challenges: limited history and examination due to the patient's mental status, broad differential diagnosis of systemic and neurologic etiologies, low yield of neurodiagnostic testing due to the high base rate of systemic causes, and the importance of identifying less common neurologic causes of encephalopathy that can be life-threatening if not identified and treated. This article discusses the differential diagnosis of acute encephalopathy, presents an approach to the history and examination in a patient with encephalopathy, reviews the literature on the yield of neurodiagnostic testing in this population, and provides a diagnostic framework for the evaluation of patients with altered mental status.

Assessment of Potential Drug-Drug Interactions of Psycholeptics and Antidepressants in Outpatient Settings

Mental health is an important segment in preserving overall health and represents a significant public health issue. In modern times, mental health disorders have risen, often requiring complex pharmacotherapy and chronic monitoring. The aim of this research was to determine the prevalence and clinical significance of potential psychotropic drug interactions in outpatient settings and compare the differences in potential drug-drug interaction (pDDIs) exposure with age. The psychotropic drugs included antipsychotics-N05A, anxiolytics-N05B, hypnotics and sedatives-N05C, and antidepressants-N06A. This retrospective study analyzed prescribed pharmacotherapy in 492 outpatients who were treated with at least one psychotropic drug. We determined 1.64 prescribed psychotropic drugs per patient and 2.2 pDDIs that involved psychotropic drugs. In total, 2285 pDDIs were recorded, of which almost half (47.6%) were pDDIs with psychotropic drugs. More prescribed psychotropic drugs were found in patients younger than 65 years, and equal exposure to pDDIs of psychotropic drugs (p = 0.5077) was found in both age groups. The most commonly identified psychotropics involved in pDDIs were benzodiazepines, promazine, and zolpidem. The results indicate that psychotropic drug interactions represent important drug-related problems for primary health care. The widespread use of psychotropic drugs and the determined clinical significance of their interactions require pharmacist interventions which can reduce the prevalence of pDDIs and increase patient safety.

Predictors of Serotonin Syndrome in Acute Poisoning with 5-Hydroxytryptamine Modulators

5-Hydroxytryptamine (5-HT) modulators are commonly prescribed medications with potentially life-threatening outcomes, particularly serotonin syndrome (SS). Early prediction of SS is critical not only to avoid lethal drug combinations but also to initiate appropriate treatment. The present work aimed to recognize the significant predictors of SS through a retrospective cross-sectional study that was conducted among patients exposed to an overdose of 5-HT modulators and admitted to a poison control center where 112 patients were enrolled. Of them, 21 patients were diagnosed with SS, and 66.7% of patients with SS were exposed to long-term co-ingestion. There was a noticeable surge in SS between April and May, and 52.4% of patients who suffered from SS were admitted after suicidal exposure (p < 0.05). Patients with SS showed severe presentation indicated by high-grade poison severity scores (PSS) and low Glasgow coma scales (GCS). PSS was a significant predictor of SS with an area under the curve of 0.879. PCO2, pulse, GCS, HCO3, and erythrocytic count were other significant predictors of SS. Combinations of serotonergic agents increase the likelihood of developing SS. Clinicians should be vigilant when prescribing a combination of serotonergic therapy, particularly for patients on illicit sympathomimetic and over-the-counter medications like dextromethorphan.

Serotonin syndrome presenting as acute dizziness with supine hypertension and orthostatic hypotension

Serotonin syndrome (SS) is a drug-induced clinical syndrome characterised by a combination of cognitive, neuromuscular and autonomic dysfunctions. The symptoms may include mild non-specific symptoms such as tremors and diarrhoea to coma and sudden death. Herein, we describe a case of SS in which acute dizziness was associated with supine hypertension and orthostatic hypotension. A man in his mid-30s had a 10-month history of anxiety, depression and chronic tension-type headache. He had been on amitriptyline (25 mg daily) and sertraline (50 mg daily). Increment of sertraline (75 mg daily) and amitriptyline (75 mg daily) and the addition of tramadol led to the development of acute severe dizziness. Physical examinations demonstrate supine hypertension and orthostatic hypotension. He also met the diagnostic criteria of SS. The administration of cyproheptadine provided a complete response to dizziness, supine hypertension, orthostatic hypotension and other clinical features of SS.

Identification of micro-recurrent lesions using methylene blue for mediastinal ectopic parathyroid adenoma: a case report

BACKGROUND

Mediastinal ectopic parathyroid adenomas are rare, and several methods are used to diagnose and localize them preoperatively. Technetium-99m methoxy isobutyl isonitrile scintigraphy has been used to diagnose parathyroid tumors. However, it is difficult to identify tumors buried in adipose tissue during surgery.

CASE PRESENTATION

We report a case in which methylene blue effectively identified small recurrent lesions in a mediastinal ectopic parathyroid adenoma. After intravenous injection of methylene blue prior to surgery, the stained parathyroid adenoma was easily identifiable. Additionally, we identified other small recurrent lesions that could not be confirmed on preoperative imaging using real-time in vivo imaging guidance during surgery. Using this strategy, complete macroscopic resection can be performed during video-assisted thoracic surgery.

CONCLUSION

Preoperative intravenous methylene blue injection is useful for identifying small recurrent lesions, even in cases of mediastinal ectopic parathyroid adenoma with suspected recurrence.

Assessment of Sumatriptan on Sepsis-Induced Kidney injury in the Cecal Ligation and Puncture Mice Model

Sepsis is a severe systemic inflammatory response with high mortality rate resulting from different microorganisms. Cytokines activation is essential for the immune response, but in painful conditions like sepsis, cytokines act as a double-edged sword and dysregulate immune response which is life-threatening owing to multiple organ dysfunction. The abnormality in 5-HT function is involved in pathological conditions like irritable bowel syndrome, inflammation, myocardial ischemia, itch and renal injury. Sumatriptan, a 5-HT_1B/1D agonist, has anti-inflammatory and anti-oxidative stress effects on animal models. This study was aimed to assess the effects of sumatriptan on kidney injury, the levels of pro-inflammatory cytokines and the percentage of survival in (CLP)-induced sepsis were examined.Cecal ligation and puncture (CLP) model was done on adult C57BL/6 male mice to induce Polymicrobial sepsis. Sumatriptan was injected intraperitoneally 1 h after the sepsis induction by CLP at doses of 0.1, 0.3, and 1 mg/kg in 3 treatment groups. To study the effect of sumatriptan on short-term survival, septic animals were detected 72 h after CLP. Serum levels of TNF-α, IL-1β, IL-6 and IL-10 were evaluated. To study sepsis-induced acute renal failure, kidney functional biomarkers and histopathological alterations were evaluated.Sumatriptan (0.3 mg/kg) administration significantly enhanced survival rate (P<0.01) compared to the CLP group. The beneficial effects of sumatriptan were related to a significant decrease in the pro-inflammatory cytokines and elevated level of IL-10. Sumatriptan presented protective effects on kidney biomarkers and histopathology assay.Anti-inflammatory effects of sumatriptan lead to decrease mortality rate and inflammatory cytokines in CLP induction sepsis in C57BL/6 mice.

Antiepileptic drugs and serotonin syndrome- A systematic review of case series and case reports

Serotonin syndrome (SS) is a drug‑induced, potentially fatal, clinical syndrome resulting from drugs that have serotonergic properties. Several antiepileptic drugs (AEDs) are known to have serotonergic properties and it can be hypothesized that such AEDs can cause SS. This study aims to review the literature on SS in patients receiving AEDs. We performed a systematic review of Scopus and MEDLINE/PUBMED for case reports and case series of SS where patients had received at least one AED at the onset of symptoms. The cases published in the English literature between 1 January 1991 and 1 April 2021 were included. Initial search identified 1263 articles of which 63 (76 patients) were included in the final analysis. Most of the included cases (53 cases, 70%) have been published in the last 10 years. The mean age of the 76 patients was 40.6 ± 17.8 years, and 51% of cases were females. These patients had been exposed to a total of 8 different types of AEDs. Valproic acid was the most common drug (29, 38%), followed by lamotrigine (22, 29%), gabapentin (16, 21%), pregabalin (seven, 9%), topiramate (five, 7%) and carbamazepine (two, 3%). There has been one case each with phenytoin and oxcarbazepine. Seven (9%) patients received more than one AEDs. Most patients (67, 88%) also received other serotoninergic agents. Only nine (12%) patients were on AEDs alone. The most common clinical condition for using AEDs was psychiatric disorders (36 patients, 47.3%), followed by migraine (17, 22.4%), other painful conditions (15, 19.7%), epilepsy (7, 9.2%), and perioperative conditions (8, 10.5%). Death was reported in two patients. We suggest that AEDs, because of their serotonergic properties, may induce SS, especially in patients who are on another serotonergic agent.

Lifetime evolution of ADHD treatment

Attention-deficit hyperactivity disorder (ADHD), has been traditionally considered a neurodevelopmental disorder affecting children and adolescents characterized by inattention, hyperactivity, disruptive behavior, and impulsivity. Although still debated, it is evident that ADHD is also present in adulthood, but this diagnosis is rarely carried out, mainly for the frequent comorbidity with other psychiatric and/or substance abuse disorders. Given the need to shed more light on the pharmacological treatment of ADHD, we performed a naturalistic review to review and comment on the available literature of ADHD treatment across the lifespan. Indeed, stimulants are endowed of a prompt efficacy and safety, whilst non-stimulants, although requiring some weeks to be fully effective, are useful when a substance abuse history is detected. In any case, the pharmacological management of ADHD appears to be still largely influenced by the individual experience of the clinicians. Further longitudinal studies with a careful and detailed characterization of participants across different phases of the lifespan are also required to provide relevant confirmations (or denials) regarding pharmacological treatments amongst the different age groups.

Preclinical support for the therapeutic potential of zolmitriptan as a treatment for cocaine use disorders

Serotonin 1B receptor (5-HT_1BR) agonists enhance cocaine intake in rats during daily self-administration but attenuate cocaine intake after prolonged abstinence. Here we investigated whether the less selective but clinically available 5-HT_1D/1BR agonist, zolmitriptan, produces similar effects. Male and free-cycling female Sprague-Dawley rats were trained to lever press for cocaine (0.75 mg/kg, i.v.) or sucrose (45 mg pellet) reinforcement until performance rates stabilized. Rats then received zolmitriptan (3.0, 5.6, and 10 mg/kg, s.c.) prior to testing for its effects on response and reinforcement rates. Under cocaine testing conditions, rats had access to the training dose for the first hour followed by a lower cocaine dose (0.075 mg/kg, i.v.) for the second hour. Zolmitriptan decreased cocaine intake at both cocaine doses and in both sexes even without a period of abstinence and without altering sucrose intake. A separate group of rats underwent identical training procedures and were tested for effects of the selective 5-HT_1B and 5-HT_1D receptor antagonists, SB224289 (3.2, 5.6, and 10 mg/kg, s.c.) and BRL15572 (0.3, 1.0, and 3.0 mg/kg, i.p.), respectively, alone or in combination with zolmitriptan (5.6 mg/kg, s.c.) under identical cocaine testing procedures as above. The zolmitriptan-induced decrease in cocaine intake was reversed by SB224289 and to a lesser extent by BRL15572, suggesting that the effects of zolmitriptan involve both 5-HT_1B and 5-HT_1D receptors. Neither zolmitriptan, SB224289, or BRL15572 altered locomotor activity at the doses effective for modulating cocaine intake. These findings suggest that zolmitriptan has potential for repurposing as a treatment for cocaine use disorders.

Analgesia in acute ischemic chest pain

Analgesics, particularly opioids, have been routinely used in the emergency treatment of ischemic chest pain for a long time. In the past two decades; however, several studies have raised the possibility of the harmful effects of opioid administration. In 2014, the American Heart Association (AHA)/American College of Cardiology Foundation (ACCF) changed the guidelines regarding the use of opioids from class IC to class IIb for non-ST elevation acute coronary syndrome. And in 2015, the European Society of Cardiology (ESC) guidelines incidentally noted the side effects of opioids. In ST-segment elevation myocardial infarction, both ESC and AHA/ACCF still recommend the use of opioids. Given the need for adequate pain relief in ischemic chest pain in the emergency setting, it is necessary to understand the adverse effects of analgesia, while still providing sufficiently potent options for analgesia. The primary purpose of this review is to quantify the effects of analgesics commonly used in the prehospital and emergency department in patients with ischemic chest pain.

A 5-year single-centre retrospective study of potential drug interactions in burns inpatients with psychiatric comorbidities

INTRODUCTION

Burns patients with psychiatric comorbidities may be at increased risk of harm from drug interactions. We aimed to identify the most common classes of drug involved, the potential clinical effects and any clinical evidence for their occurrence.

METHODS

The International Burn Injury Database was used to identify all admission episodes for patients with a psychiatric comorbidity over a 5-year period at an adult regional burns unit. For this group, all drugs administered were categorised as either a new or continuing medication. Following this, an established online tool was used to screen for potential interactions between drugs. Where one was identified, a retrospective notes review was used to investigate whether it had occurred clinically.

RESULTS

Ninety-one admission episodes were identified and records were available for 60 of these. In total, 145 incidences of severe potential interactions were identified (89 between a new drug and a continuing drug and 56 between two new drugs). The most frequently involved continuing drugs with the potential for interaction were neurotransmitter reuptake-inhibiting antidepressants and mirtazapine, while the most common new drugs identified were ondansetron, fentanyl and tramadol. The most frequently identified potential consequence of interactions were serotonin syndrome, arrhythmias and hypokalaemia. Clinically, there was minimal evidence for any interaction.

CONCLUSION

We have found many potential severe interactions in this patient group and psychotropic drugs were more commonly implicated than other drug classes. However, there was little evidence of the clinical manifestations of interaction. Serious drug interactions in burns patients are likely rare, but clinicians should be aware of the most likely drugs involved and the possible sequelae.

ADHD with Comorbid Bipolar Disorders: A Systematic Review of Neurobiological, Clinical and Pharmacological Aspects Across the Lifespan

BACKGROUND

Attention deficit hyperactivity (ADHD) disorder is a neurodevelopmental disorder characterized by inattention, hyperactivity, disruptive behaviour, and impulsivity. Despite considered typical of children for a long time, the persistence of ADHD symptoms in adulthood gained increasing interest during the last decades. Indeed, its diagnosis, albeit controversial, is rarely carried out even because ADHD is often comorbid with several other psychiatric diosrders, in particular with bipolar disorders (BDs), a condition that complicates the clinical picture, assessment and treatment.

AIMS

The aim of this paper was to systematically review the scientific literature on the neurobiological, clinical features and current pharmacological management of ADHD comorbid with BDs across the entire lifespan, with a major focus on the adulthood.

DISCUSSION

The pharmacology of ADHD-BD in adults is still empirical and influenced by the individual experience of the clinicians. Stimulants are endowed of a prompt efficacy and safety, whilst non-stimulants are useful when a substance abuse history is detected, although they require some weeks in order to be fully effective. In any case, an in-depth diagnostic and clinical evaluation of the single individual is mandatory.

CONCLUSION

The comorbidity of ADHD with BD is still a controversial matter, as it is the notion of adult ADHD as a distinct nosological category. Indeed, some findings highlighted the presence of common neurobiological mechanisms and overlapping clinical features, although disagreement does exist. In any case, while expecting to disentangle this crucial question, a correct management of this comorbidity is essential, which requires the co-administration of mood stabilizers. Further controlled clinical studies in large samples of adult ADHD-BD patients appear extremely urgent in order to better define possible therapeutic guidelines, as well as alternative approaches for this potentially invalidating condition.

Serotonin Syndrome: Pathophysiology, Clinical Features, Management, and Potential Future Directions

Serotonin syndrome (SS) (also referred to as serotonin toxicity) is a potentially life-threatening drug-induced toxidrome associated with increased serotonergic activity in both the peripheral (PNS) and central nervous systems (CNS). It is characterised by a dose-relevant spectrum of clinical findings related to the level of free serotonin (5-hydroxytryptamine [5-HT]), or 5-HT receptor activation (predominantly the 5-HT_1A and 5-HT_2A subtypes), which include neuromuscular abnormalities, autonomic hyperactivity, and mental state changes. Severe SS is only usually precipitated by the simultaneous initiation of 2 or more serotonergic drugs, but the syndrome can also occur after the initiation of a single serotonergic drug in a susceptible individual, the addition of a second or third agent to long-standing doses of a maintenance serotonergic drug, or after an overdose. The combination of a monoamine oxidase inhibitor (MAOI), in particular MAO-A inhibitors that preferentially inhibit the metabolism of 5-HT, with serotonergic drugs is especially dangerous, and may lead to the most severe form of the syndrome, and occasionally death. This review describes our current understanding of the pathophysiology, clinical presentation and management of SS, and summarises some of the drugs and interactions that may precipitate the condition. We also discuss the newer novel psychoactive substances (NPSs), a growing public health concern due to their increased availability and use, and their potential risk to evoke the syndrome. Finally, we discuss whether the inhibition of tryptophan hydroxylase (TPH), in particular the neuronal isoform (TPH2), may provide an opportunity to pharmacologically target central 5-HT synthesis, and so develop new treatments for severe, life-threatening SS.

Management of Trazodone Overdose with Severe Hypotension

Trazodone is a medication that possesses antidepressant, anxiolytic, and hypnotic properties. Its mechanism of action includes blockade of serotonin type 2 receptors, weak inhibition of serotonin reuptake, blockade of histamine 1 receptors, and blockade of alpha-1-adrenergic receptors. We present a case of intentional ingestion of an estimated 2500 mg of trazodone leading to persistent hypotension, requiring aggressive fluid resuscitation, pressor support, and intensive care unit admission. Complications associated with trazodone overdoses are significant and clinicians should be aware of the associated symptoms and necessary management plans necessary for such ingestions.

Therapeutic Drug Monitoring of Antidepressants

For a number of antidepressants in current clinical use, concentrations in serum or plasma are a more reliable index of target drug concentrations than is dosage. For such drugs, therapeutic drug monitoring (TDM) may be a useful clinical guide for the purpose of maximizing the likelihood of favorable therapeutic outcome while minimizing the probability of clinical ineffectiveness or adverse side effects. TDM is of greatest benefit when a therapeutic range of serum concentrations has been well established. Even if such a range is not definitively determined, TDM can be of help in situations in which patients are refractory to therapy despite adequate or high dosages, when adverse events supervene even with low doses, or when noncompliance with the intended dosage plan is suspected. Serum antidepressant concentrations from TDM should be interpreted in the full context of the patient's demographic characteristics and clinical status, along with an understanding of the pharmacokinetics of the medication being taken, the timing of the sample in relation to the dosage regimen, and the specific laboratory assay procedure. TDM measurements may be costly, and the potential benefits of the information need to be weighed against the cost to the patient or to the health care system.

Headache in the presentation of noncephalic acute illness

Background:

Headache is a frequent symptom of many systemic diseases that do not involve cranial structures. In this observational study, we assessed factors associated with headache in the acute presentation of systemic conditions in a nonsurgical emergency department (ED).

Methods:

Consecutive patients, admitted to Soroka University Medical Center ED due to noncephalic illness, were prospectively surveyed using a structured questionnaire focused on the prevalence and characteristics of headache symptoms. Medical data were extracted from the patient's charts.

Results:

Between 1 and 6/2012, 194 patients aged 64.69 ± 19.52 years, were evaluated. Headache was reported by 83 (42.7%) patients and was more common among patients with febrile illness (77.5% vs. 22.5%, P < 0.001). Respiratory illness and level of O₂ saturation were not associated with headache. Headache in the presentation of a noncephalic illness was associated with younger age (58 vs. 69, P < 0.001) and with suffering from a primary headache disorder (48.2% vs. 10.8%, P < 0.001). Headache was also associated with higher body temperature and lower platelets count.

Conclusions:

Headache is a common symptom in acute noncephalic conditions and was found to be associated with younger age and febrile disease on presentation. Patients who present with primary headache disorders are more prone to have headache during acute illness. Acute obstructive respiratory disease, hypercarbia or hypoxemia were not associated with headache.

Combining Stimulants and Monoamine Oxidase Inhibitors: A Reexamination of the Literature and a Report of a New Treatment Combination

This report reviews the medical literature on combining stimulants with monoamine oxidase inhibitors. A case is also presented documenting successful treatment of major depressive disorder and comorbid attention-deficit/hyperactivity disorder using the previously undocumented combination of transdermal selegiline and lisdexamfetamine. This combination should be used cautiously and with ongoing monitoring of heart rate and blood pressure.

Art and dystonia

Dystonia has a recent history in medicine. Focal dystonia was described in the 19th century by classic authors including Gowers, whilst generalized dystonia was described at the turn of the century. However, it is possible to find precise descriptions of dystonia in art, centuries before the medical definition. We have reviewed several pieces of art (sculpture, painting and literature) across the history that might represent descriptions of dystonia, from ancient period to nowadays. In classic times, the first reference to abnormal postures can be tracked back to the new Empire of Egypt (equinus foot), not to mention some recently described examples of dystonia from the Moche sculptures in Peru or Veracruz culture from Mexico. In Middle Ages it is possible to find many examples of sculptures in European cathedrals representing peasants with dramatic, presumably dystonic postures that coexist with amputation of limbs. This unique combination of dystonia and limb amputation probably represents ergotism. The painters Brueghel, Ribera and Velazquez also represented figures with postures likely to be dystonic. Literature is also a source of precise pre-neurological descriptions, especially during the 19th century. In David Copperfield, Dickens depicts characters with generalized dystonia (Uriah Heep), cervical dystonia (Mr. Sharp) and spasmodic dysphonia (Mr Creakle). Finally, even in modern Art (19th and 20th centuries), there are dramatic descriptions of abnormal postures that are likely to be dystonic, such as painful cervical dystonia (Brancusi), cervical dystonia with sensory trick (Modigliani) and upper limb dystonia (Wyspianski). However some postures presented in works of art may simply be a form of artistic expression and only bear unintentional resemblance to the dystonic postures. Art may be a source of neurological information, and that includes primary and secondary dystonia.

Serotonin Syndrome in the Setting of Lamotrigine, Aripiprazole, and Cocaine Use

Serotonin syndrome is a potentially life-threatening condition associated with increased serotonergic activity in the central nervous system. It is classically associated with the simultaneous administration of two serotonergic agents, but it can occur after initiation of a single serotonergic drug or increasing the dose of a serotonergic drug in individuals who are particularly sensitive to serotonin. We describe a case of serotonin syndrome that occurred after ingestion of higher than prescribed doses of lamotrigine and aripiprazole, in addition to cocaine abuse. The diagnosis was established based on Hunter toxicity criteria and severity was classified as mild. The features of this syndrome resolved shortly after discontinuation of the offending agents. Serotonin syndrome is characterized by mental status changes, autonomic hyperactivity, and neuromuscular abnormalities along a spectrum ranging from mild to severe. Serotonin syndrome in our patient was most likely caused by the pharmacokinetic and pharmacodynamic interactions between lamotrigine, aripiprazole, and cocaine leading to increased CNS serotonergic activity.

A case of the serotonin syndrome secondary to phenelzine monotherapy at therapeutic dosing

A 27-year-old Caucasian female with a history of depression was admitted to our local hospital with vague events that occurred a day before. This included an episode of dysarthria, and unsteadiness, followed by feeling generally unwell. Two weeks prior to presentation she was commenced on phenelzine. During clinical assessment she suddenly deteriorated with a dramatic fall in her conscious level. Moreover, she became hyperthermic, tachycardic, and diaphoretic, and developed increased tone in all muscles and ocular clonus. Rectal diazepam was administered but failed to control the symptoms. Consequently, she was transferred to the intensive care unit for intubation and muscle relaxants were commenced. She responded well and recovered next day without complications. Her symptoms and signs were consistent with the serotonin syndrome with phenelzine being the likely cause. To the best of our knowledge, this is the first reported case to associate the condition with phenelzine alone at therapeutic dose.

Aquatic blues: modeling depression and antidepressant action in zebrafish

Depression is a serious psychiatric condition affecting millions of patients worldwide. Unipolar depression is characterized by low mood, anhedonia, social withdrawal and other severely debilitating psychiatric symptoms. Bipolar disorder manifests in alternating depressed mood and 'hyperactive' manic/hypomanic states. Animal experimental models are an invaluable tool for research into the pathogenesis of bipolar/unipolar depression, and for the development of potential treatments. Due to their high throughput value, genetic tractability, low cost and quick reproductive cycle, zebrafish (Danio rerio) have emerged as a promising new model species for studying brain disorders. Here, we discuss the developing utility of zebrafish for studying depression disorders, and outline future areas of research in this field. We argue that zebrafish represent a useful model organism for studying depression and its behavioral, genetic and physiological mechanisms, as well as for anti-depressant drug discovery.

Side effect profile of 5-HT treatments for Parkinson's disease and L-DOPA-induced dyskinesia in rats

BACKGROUND AND PURPOSE

Treatment of Parkinson's disease (PD) with L-DOPA eventually causes abnormal involuntary movements known as dyskinesias in most patients. Dyskinesia can be reduced using compounds that act as direct or indirect agonists of the 5-HT1 A receptor, but these drugs have been reported to worsen PD features and are known to produce '5-HT syndrome', symptoms of which include tremor, myoclonus, rigidity and hyper-reflexia.

EXPERIMENTAL APPROACH

Sprague-Dawley rats were given unilateral nigrostriatal dopamine lesions with 6-hydroxydopamine. Each of the following three purportedly anti-dyskinetic 5-HT compounds were administered 15 min before L-DOPA: the full 5-HT1 A agonist ±-8-hydroxy-2-dipropylaminotetralin (±8-OH-DPAT), the partial 5-HT1 A agonist buspirone or the 5-HT transporter inhibitor citalopram. After these injections, animals were monitored for dyskinesia, 5-HT syndrome, motor activity and PD akinesia.

KEY RESULTS

Each 5-HT drug dose-dependently reduced dyskinesia by relatively equal amounts (±8-OH-DPAT ≥ citalopram ≥ buspirone), but 5-HT syndrome was higher with ±8-OH-DPAT, lower with buspirone and not present with citalopram. Importantly, with or without L-DOPA, all three compounds provided an additional improvement of PD akinesia. All drugs tempered the locomotor response to L-DOPA suggesting dyskinesia reduction, but vertical rearing was reduced with 5-HT drugs, potentially reflecting features of 5-HT syndrome.

CONCLUSIONS AND IMPLICATIONS

The results suggest that compounds that indirectly facilitate 5-HT1 A receptor activation, such as citalopram, may be more effective therapeutics than direct 5-HT1 A receptor agonists because they exhibit similar anti-dyskinesia efficacy, while possessing a reduced side effect profile.

Cows Come Down from the Mountains before the (Mw = 6.1) Earthquake Colfiorito in September 1997; A Single Case Study

The September-October 1997 seismic sequence in the Umbria-Marche regions of Central Italy has been one of the stronger seismic events to occur in Italy over the last thirty years, with a maximum magnitude of Mw = 6.1. Over the last three years, a collection of evidence was carried out regarding non-seismic phenomena, by interviewing local residents using a questionnaire. One particular observation of anomalous animal behaviour, confirmed by many witnesses, concerned a herd of cows, which descended from a mountain close to the streets of a village near the epicentre, a few days before the main shock. Testimonies were collected using a specific questionnaire including data on earthquake lights, spring variations, human diseases, and irregular animal behaviour. The questionnaire was compiled after the L'Aquila earthquake in 2009, and was based upon past historical earthquake observations. A possible explanation for the cows' behavior-local air ionization caused by stress-activated positive holes-is discussed.

Full recovery after severe serotonin syndrome, severe rhabdomyolysis, multi-organ failure and disseminated intravascular coagulopathy from MDMA

3, 4-methylenedioxymethamphetamine (MDMA), popularly known as "ecstasy" is a synthetic, psychoactive drug used recreationally for its euphoric and "energy increasing" effects. MDMA has been linked to several severe adverse effects including the development of serotonin syndrome and sudden death. Individuals of Asian descent have been shown to have a predisposition for these severe adverse effects. We present a case of a young Asian-American male who following MDMA ingestion presented with severe rhabdomyolysis (CK 130,350 U/L), multiple organ failure and severe serotonin syndrome with one of the highest recorded temperatures '108.9 °F (42.7 °C)' in a survivor of severe serotonin syndrome. The patient initially received supportive care including ventilatory support; he eventually needed hemodialysis, but went on to make a full recovery within 3 weeks. This case shows and emphasizes the importance of 'aggressive' supportive care on patient prognosis particularly for patients on the extreme end of the serotonin syndrome.

Linezolid is associated with serotonin syndrome in a patient receiving amitriptyline, and fentanyl: a case report and review of the literature

We report a unique case of an adverse interaction between the oxazolidinone antibiotic linezolid, the tricyclic antidepressant amitriptyline and the opioid analgesic fentanyl in a 68-year-old woman with advanced ischemic peripheral arterial disease and sepsis, under empirical antibiotic treatment. We also summarize the current relevant literature as identified via PubMed, EMBASE, and PsycINFO as well as reference sections of selected articles.

Systematic review of intravenous methylene blue in parathyroid surgery

Background

Methylene blue is an intraoperative adjunct for localization of enlarged parathyroid glands. The availability of preoperative and other intraoperative localization methods, and the reported adverse effects of methylene blue make its routine use debatable. The aim of this study was to perform a systematic review of the use of methylene blue in parathyroidectomy.

Methods

A systematic review of English-language literature in MEDLINE and Scopus databases on the use of intravenous methylene blue in parathyroid surgery was carried out.

Results

There were no randomized clinical trials. Thirty-nine observational studies were identified, of which 33 did not have a control arm. The overall median staining rate for abnormal parathyroid glands was 100 per cent. The median cure rates in the methylene blue and no-methylene blue arms were 100 and 98 per cent respectively. Neurotoxicity was reported in 25 patients, all of whom were taking serotonergic medication.

Conclusion

Observational evidence suggests that methylene blue is efficacious in identifying enlarged parathyroid glands. Toxicity appears to be mild in the absence of concomitant use of serotonin reuptake inhibitors. The effectiveness of methylene blue in the context of currently used preoperative and intraoperative localization techniques has yet to be shown.

Recognition and management of perioperative serotonin syndrome

Mild forms of serotonin syndrome can potentially be fatal, if not recognized. The increased use of serotonergic agents makes the awareness of its prevalence, various presentations, diagnostic evaluation, and treatment a clinical imperative. It is important to note that serotonin syndrome can only be diagnosed clinically in the presence of 3 clinical criteria: mental status changes, autonomic manifestations, and neuromuscular abnormalities. This case report describes a patient who underwent an uncomplicated closed nasal fracture reduction and subsequently developed serotonin syndrome.

[Perioperative adverse events related to antidepressive agents use]

OBJECTIVE

Depression is the most common psychiatric disease, which is treated by the use of antidepressive agents possessing various mechanisms of action. Thus, the use in preoperative period of antidepressive agents is frequent (7% of patients scheduled for surgery). The objective of this review was to update the knowledge on the drug interactions between antidepressive agents and drugs used in perioperative period.

METHODS

(i) Medline and Ovid databases using combination of antidepressive agent and perioperative period as keywords; (ii) national and European epidemiologic database; (iii) expert recommendation and official French health agency; (iv) reference book chapters.

RESULTS

The clinical practice showed a limited risk of adverse event related to antidepressant agents interaction with perioperative used drugs. In the two past decades, few relevant observations of adverse event related with imipramine and monoamine oxidase inhibitors use was reported. The most recent antidepressive agents had no serious adverse interaction. Nevertheless, the serotonin syndrome has to be known as far as it is more and more reported. In case of hypotension, the use of vasopressive agent has to be careful because of excessive response.

Serotonin toxicity: a short review of the literature and two case reports involving citalopram

The serotonin toxicity (ST) is a potentially life-threatening adverse drug reaction results from therapeutic drug use, intentional self-poisoning, or inadvertent interactions between drugs. ST can be caused by a single or a combination of drugs with serotonergic activity due to excessive serotonergic agonism on central nervous system and peripheral serotonergic receptors (monoamine oxidase inhibitors, tricyclic antidepressants, SSRIs, opiate analgesics, over-the-counter cough medicines, antibiotics, weight-reduction agents, antiemetics, antimigraine agents, drugs of abuse, H2-antagonist and herbal products). The serotonin toxicity is often described as a clinical triad of mental-status changes (agitation and excitement with confusion), autonomic hyperactivity (diaphoresis, fever, tachycardia, and tachypnea), neuromuscular abnormalities (tremor, clonus, myoclonus, and hyperreflexia) and, in the advanced stage, spasticity; not all of these findings are consistently present. In this article, we describe two cases of ST due to interaction between Citalopram and two CYP2D6 inhibitors: Cimetidine and Topiramate and their clinical resolution after treatment discontinuation.

Recommendations for the proper use of nonprescription cough suppressants and expectorants in solid-organ transplant recipients

OBJECTIVE

To describe the pharmacology and safety of oral over-the-counter cough suppressants and expectorants and to present recommendations for the use of these agents in solid-organ transplant recipients based on the potential for adverse drug reactions or drug-disease interactions.

DATA SOURCES AND EXTRACTION

Data from journal articles and other sources describing the pharmacology and safety of over-the-counter cough suppressants and expectorants, drug-drug interactions with immunosuppressive agents, and drug-disease state interactions are reviewed.

DATA SYNTHESIS

Potential and documented drug-drug interactions between immunosuppressive agents and over-the-counter cough medications guaifenesin, dextromethorphan, diphenhydramine, and codeine were evaluated on the basis of pharmacokinetic and pharmacodynamic principles. Interactions between these cough medications and the physiological changes in the body following transplantation also were examined.

CONCLUSION

Diphenhydramine requires additional monitoring when used to treat cough in transplant recipients owing to its anticholinergic properties and the potential for interactions with cyclosporine. Dextromethorphan can be used in most transplant recipients, although greater caution should be exercised if the patient has undergone liver transplant or has liver impairment. Guaifenesin can be used in transplant recipients but should be used with caution in patients receiving kidney or lung transplants and in patients with renal impairment. Codeine combined with guaifenesin is another option for cough and can be used in most transplant patients although those with reduced renal function should be monitored carefully for adverse events.

Recommendations for the Proper Use of Nonprescription Cough Suppressants and Expectorants in Solid-Organ Transplant Recipients

Objective

To describe the pharmacology and safety of oral over-the-counter cough suppressants and expectorants and to present recommendations for the use of these agents in solid-organ transplant recipients based on the potential for adverse drug reactions or drug-disease interactions.

Data Sources and Extraction

Data from journal articles and other sources describing the pharmacology and safety of over-the-counter cough suppressants and expectorants, drug-drug interactions with immunosuppressive agents, and drug-disease state interactions are reviewed.

Data Synthesis

Potential and documented drug-drug interactions between immunosuppressive agents and over-the-counter cough medications guaifenesin, dextromethorphan, diphenhydramine, and codeine were evaluated on the basis of pharmacokinetic and pharmacodynamic principles. Interactions between these cough medications and the physiological changes in the body following transplantation also were examined.

Conclusion

Diphenhydramine requires additional monitoring when used to treat cough in transplant recipients owing to its anticholinergic properties and the potential for interactions with cyclosporine. Dextromethorphan can be used in most transplant recipients, although greater caution should be exercised if the patient has undergone liver transplant or has liver impairment. Guaifenesin can be used in transplant recipients but should be used with caution in patients receiving kidney or lung transplants and in patients with renal impairment. Codeine combined with guaifenesin is another option for cough and can be used in most transplant patients although those with reduced renal function should be monitored carefully for adverse events.

Serotonin syndrome in an orthopaedic patient secondary to linezolid therapy for MRSA infection

A 67-year-old patient was admitted for incision and drainage of a recurrent methicillin-resistant Staphylococcus aureus (MRSA) hip abscess. Linezolid therapy was initiated postoperatively. Within 48 h the patient developed confusion, agitation, hypertension and acute renal failure. Citalopram was stopped and resolution of symptoms occurred within 48 h of discontinuing the offending agent. The symptoms observed in our patient were consistent with the Sternbach criteria for serotonin syndrome.

Patients presenting with acute toxin ingestion

Organ toxicity caused by poisons or drug therapy is diverse and may not be commonly encountered clinically. In general, commonly encountered conditions caused by drug/toxin pharmacology can be classified into 7 categories by shared mechanisms of organ injury. This review of drug/toxin-induced injury discusses drug or toxin-induced pathology that the clinician may encounter and therapeutic approaches to these syndromes.

Serotonin syndrome risks when combining SSRI/SNRI drugs and triptans: is the FDA's alert warranted?

In 2006 the Food and Drug Administration (FDA) issued an alert, based on 27 case reports gathered over a 5-year span, regarding serotonin syndrome resulting from concurrent use of either a selective serotonin-reuptake inhibitor (SSRI) or a selective serotonin/norepinephrine reuptake inhibitor (SNRI) with a triptan. These diagnoses have been subsequently challenged as not meeting validated criteria for serotonin syndrome, in part because the FDA has yet to publicly disseminate important case report data. As a result of the FDA's alert, some clinicians are reluctant or refuse to provide these drugs concomitantly to patients. We believe that withholding these medications due to fears of serotonin syndrome is difficult to justify. In contrast to the small number of case reports, research shows that approximately 700,000 patients annually take SSRIs or SNRIs with triptans and that this drug combination has been effectively used by millions of individuals over the past decade. We encourage healthcare professionals to familiarize themselves with data on serotonin syndrome and to administer SSRIs/SNRIs with triptans when clinically appropriate.

Drug-induced serotonin syndrome: a review

Serotonin syndrome, or serotonin toxicity (ST), is a clinical condition that occurs as a result of an iatrogenic drug-induced increase in intrasynaptic serotonin levels primarily resulting in activation of serotonin(2A) receptors in the central nervous system. The severity of symptoms spans a spectrum of toxicity that correlates with the intrasynaptic serotonin concentration. Although numerous drugs have been implicated in ST, life-threatening cases generally occur only when monoamine oxidase inhibitors are combined with either selective or nonselective serotonin re-uptake inhibitors. The triad of clinical features consists of neuromuscular hyperactivity, autonomic hyperactivity and altered mental status, which may present abruptly and progress rapidly. The awareness of ST is crucial not only in avoiding the unintentional lethal combination of therapeutic drugs but also in recognizing the clinical picture when it occurs so that treatment can be promptly initiated. In this review, the pathophysiology, clinical features, implicated drugs, diagnosis and treatment of ST are discussed.

Current status of symptomatic medical therapy in Parkinson's disease

Symptomatic medical therapies for Parkinson's disease (PD) have been disease modifying and have led to improvement in daily function, quality of life, and survival. For 40 years, these therapies have been primarily dopaminergic, and currently include the dopamine (DA) precursor levodopa (LD), DA agonists, catechol-O-methyltransferase (COMT) inhibitors, and monoamine oxidase (MAO) inhibitors. The roles of all these classes of agents have evolved, with significant changes occurring since the early 2000s. This article reviews the current literature for each of these classes of drugs, with a focus on efficacy and place in the therapeutic scheme. Levodopa is no longer considered to be toxic and, thus, its early use is not only appropriate but recommended. Ergot agonists are no longer in use, and new agents administered in patch form or subcutaneous injections have been approved. The COMT inhibitor tolcapone, with its significant efficacy, has been reintroduced, and two new MAO inhibitors have been approved. Selected safety issues are discussed, including the incidence of melanoma in relation to LD; pathological gambling and DA agonists; hepatic toxicity of tolcapone; and the tyramine or so-called cheese reaction with MAO B inhibitors. The article closes with a discussion of future directions and new drugs under development.

Differential behavioral syndrome evoked in the rats after multiple doses of SSRI fluoxetine with selective MAO inhibitors rasagiline or selegiline

This study investigated whether rasagiline and selegiline (MAO-B inhibitors) induce serotonin syndrome in fluoxetine-treated rats. Rats received rasagiline (0.1, 0.5, 2.0 mg/kg), or selegiline (0.8, 4.0, 16.0 mg/kg) (doses reflecting the clinical ratio of 1:8 base) in drinking water for 28 days. During the last 21 days, they received injections of fluoxetine 10 mg/kg (controls received water only, then saline injections; a fluoxetine only group received water only then fluoxetine). Serotonin syndrome was assessed using neurological severity score (NSS), food intake and weight gain. Mean NSS significantly increased, and weight and food consumption significantly decreased in rats receiving fluoxetine alone compared with controls. Selegiline 16 mg/kg but not rasagiline (regardless of dose) exacerbated these effects. We concluded that selegiline's amphetamine-like metabolites may increase synaptic cathecholamines and possibly serotonin, aggravating fluoxetine's effect. Rasagiline is devoid of this effect and may therefore be safer for use with serotonergic drugs in parkinsonian patients.

Serotonin syndrome in elderly patients treated for psychotic depression with atypical antipsychotics and antidepressants: two case reports

We report two cases of serotonin syndrome in elderly patients during treatment of psychotic depression with atypical antipsychotics and antidepressants. The first case is a 69-year-old man who was admitted for depression with psychosis and treated with trazodone, risperidone, and sertraline. Subsequently, he developed myoclonus, tremor, cogwheel rigidity, and diaphoresis. The second case is a 72-year-old female initially admitted to a medical inpatient unit for a change in mental status that presented as increased confusion, lethargy, slurred speech, and a fever of 101.5 degrees. She had been on phenelzine and quetiapine. In both cases, all symptoms resolved within 24 hours of the psychotropics being stopped. In both cases, we believe that serotonin syndrome was produced by a combination of an antidepressant and an atypical antipsychotic. There have been several case reports of serotonin syndrome from similar combinations of antidepressant and atypical antipsychotic treatment. Clinicians treating elderly patients with a combination of serotonergic antidepressants and atypical antipsychotics for psychotic depression should be aware of the potential for serotonin syndrome.