This study investigated the real-world incidence rate of serotonin syndrome in patients receiving tedizolid and concomitant serotonergic agents. A retrospective cohort of 479 adult patients was assessed between January 2015 and July 2023. Overall, a rare rate of 0.4% (2/479) of possible serotonin syndrome with tedizolid was identified. Given that concomitant serotonergic agents were commonly used, further study is warranted to determine causality.

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.

UNASSIGNED: Serotonin syndrome is a rare, life-threatening toxidrome caused by serotonergic agents. This syndrome classically presents with a combination of mental status changes, autonomic hyperactivity, and neuromuscular abnormalities. However, diagnosing the condition is difficult because of its variable symptoms at presentation. As a result, serotonin syndrome often is underreported, making it harder to understand, recognize, and treat. Patients with this condition may present to primary or urgent care or an ED, and may become acutely symptomatic during an inpatient admission. Clinicians must be able to identify at-risk patients and intervene to prevent potentially lethal complications.

Serotonin syndrome is a rare but potentially fatal condition characterized by altered mental status, autonomic hyperactivity, and neuromuscular abnormalities. Although fentanyl is known to be a causative agent of serotonin syndrome, most reports have shown that fentanyl-related serotonin syndrome is caused by multiple drug interactions, and only one case of serotonin syndrome caused by fentanyl alone has been reported in a pediatric patient. In this report, we describe a case of postoperative serotonin syndrome caused by fentanyl alone in an adult patient after cardiac surgery. A 66-year-old male was diagnosed with unstable angina pectoris and underwent off-pump coronary artery bypass grafting. Two hours after the intensive care unit (ICU) admission, he exhibited symptoms of sweating, tremors, and muscle rigidity. Four hours later, the body temperature rose to 40.0 °C, suggesting malignant hyperthermia or a similar condition. Dantrolene was administered to the patient, and all symptoms improved within several minutes. However, the patient experienced a relapse of symptoms every four to six hours, requiring additional dantrolene treatment each time. Although no other serotonergic agents were used, we suspected serotonin syndrome induced by fentanyl alone and discontinued its use on postoperative day three. Following the discontinuation of fentanyl, no further episodes were observed. The patient was discharged from the hospital without any complications on postoperative day 29. During a subsequent check-up, the patient was found to have a sternal dehiscence and underwent one-stage sternal reconstruction. General anesthesia was induced and maintained without the use of fentanyl. The patient was discharged 10 days after surgery without symptoms of serotonin syndrome. In a patient with postoperative hyperthermia and neuromuscular abnormalities, serotonin syndrome should be considered when fentanyl is administered. Dantrolene may be beneficial in managing serotonin syndrome caused by fentanyl alone and/or benzodiazepine resistance.

Bronchopulmonary carcinoid tumors are rare, slow-growing malignant neuroendocrine tumors. Early diagnosis is pivotal as surgical resection is the main stay of treatment. A 40-year-old female with typical bronchial carcinoid presented with complaints of breathlessness on mild to moderate exertion, intermittent productive cough, low-grade fever, and loss of appetite since 1 year. Right lobectomy was performed with regional lymph node resection; during resection of the tumor, manipulation led to a massive surge and fluctuations in blood pressure which were managed with deepening of the plane of anesthesia and administration of nitroglycerin infusion. She was discharged home in a good condition. Typical carcinoid tumor involves the central airways causing bronchial obstruction; however, in the present case, non-specific symptomatic presentation led to late detection. The outcome of typical carcinoids even with lymph node metastasis is excellent with complete resection; however, close follow-up is recommended due to a high incidence of recurrence.

Chronic treatment with clomipramine, a tricyclic antidepressant drug, reduces symptoms of obsessive-compulsive disorder (OCD) and can influence the activity of the hypothalamic-pituitary-adrenal axis. However, little is known regarding the effects of acute clomipramine on the immediate expression of stress responses. Serotonergic drugs can elicit surfacing, a behavioral profile potentially related to toxicity in fish, although surfacing has not yet been observed after clomipramine exposure. The present study investigated the impact of acute exposure to clomipramine on basal and stress-induced behaviors in the novel tank test and cortisol levels in mixed-sex, wild-type, adult zebrafish (Danio rerio). The findings show clomipramine-exposed groups (regardless of stress exposure) spent much more time in the top of the novel tank and had significantly less overall motor activity in the behavioral task compared to the fish not exposed to the drug. Then, the dose-dependent effects of acute clomipramine on activity in the surface of the novel tank (top third of the top half) were investigated further. Clomipramine dose-dependently increased surface-dwelling and elicited a dose-dependent hypoactivity in overall motor behavior. There were no statistically significant differences in whole-body cortisol levels in either experiment. Like other serotonin-acting drugs, clomipramine strongly elicited surface-dwelling and depressed motor behavior in adult zebrafish. Additional testing is needed to elucidate whether surfacing represents a toxic state and how serotonin regulates surfacing.

Neuropsychiatric systemic lupus erythematosus (NPSLE) is a complication of systemic lupus erythematosus with diverse clinical presentations sharing common features with variable neurologic disorders. Magnetic resonance imaging (MRI) may provide imaging evidence of structural brain abnormalities associated with symptoms of NPSLE. Serotonin syndrome is a toxidrome characterized by altered mental status, autonomic hyperactivity, and neuromuscular abnormalities. It is mostly caused by medications that increase serotonin and is rarely reported as a manifestation of neuropsychiatric lupus. We presented the case of a 24-year-old Taiwanese woman with a history of systemic lupus erythematosus diagnosed at 21 years of age. The initial clinical and laboratory presentations upon diagnosis included fever, arthritis, hypocomplementemia, positive antinuclear antibody, anti-double-stranded DNA antibody, and anti-ribosomal P antibody. Her condition once remained stable under oral glucocorticoids and immunosuppressants, but she developed sudden-onset consciousness disturbance, incoherent speech, and unsteady gait ten days before our assessment. A high fever of up to 39 °C with tremor and clonus occurred at the intensive care unit. Brain MRI revealed symmetric T2 hyperintensity without diffusion restriction over the bilateral globus pallidus. High-dose pulse glucocorticoid and rituximab were prescribed during her admission and the neuropsychiatric symptoms diminished upon treatment. No alternation in mental status or involuntary movements were noted at follow-up. Our patient was diagnosed with neuropsychiatric lupus, with clinical symptoms and image findings mimicking those of serotonin syndrome. Neuroimaging, such as MRI, detects various structural brain abnormalities and may provide pathophysiological evidence of clinical manifestations.

Serotonin syndrome (toxicity), resulting from an excessive accumulation of serotonin in the central nervous system, it can occur due to various factors such as the initiation of medication, overdose or drug interactions. Diagnosing serotonin toxicity presents challenges as there are no definitive criteria. This review delves into the pathophysiology, incidence, clinical assessment and management of serotonin toxicity, stressing the significance of promptly recognizing and managing severe cases. Diagnosis relies primarily relies on clinical assessment due to the absence of specific laboratory tests. The Hunter Serotonin Toxicity criteria are commonly utilized but have only been validated in the overdose setting. Assessing the severity of toxicity is crucial for guiding management decisions. Supportive care, discontinuation of causative agents and symptomatic treatment are prioritized in management. Mild toxicity often requires withdrawal or reduction of the serotonergic agent, while more severe toxicity requires more aggressive resuscitative and supportive care. Severe serotonin toxicity characterized by hyperthermia and rigidity requires aggressive supportive measures, including benzodiazepines, intubation, paralysis and active cooling. Animal studies suggest potential benefits of 5-HT2A receptor antagonists in preventing hyperthermia and fatalities, but only at high doses. Their clinical effectiveness remains uncertain, and evidence is predominately from case series and case reports. Although commonly used, serotonin antagonists like cyproheptadine lack conclusive evidence of efficacy. Other serotonin antagonists such as chlorpromazine and olanzapine have been explored but evidence is limited to case reports. Hence, the cornerstone of treating severe cases does not lie in \'antidote\' administration or even diagnosis but in effective early resuscitative and supportive care.

UNASSIGNED: Serotonin syndrome is characterized by mental status changes, autonomic hyperactivity, and neuromuscular abnormalities. This syndrome results from various medications that engender serotonergic overactivity. Atomoxetine is a norepinephrine reuptake inhibitor used for the treatment of attention-deficit hyperactivity disorder (ADHD). Two case reports have described serotonin syndrome induced by the combination of atomoxetine with venlafaxine or methylphenidate, but no report describes this syndrome induced by atomoxetine alone. This report describes serotonin syndrome induced solely by an overdose of atomoxetine in a patient with ADHD.
UNASSIGNED: The patient in this case was a 21-year-old man who had been treated with atomoxetine for ADHD. He was transported to our hospital 1 h after intentional ingestion of 1200 mg of atomoxetine in a suicide attempt. On admission, he showed profuse diaphoresis, marked agitation, somnolence, slight fever, tachycardia, prolonged QT interval, myoclonus, tremor, and hyperreflexia. He was diagnosed as having serotonin syndrome and was treated with administration of activated charcoal and massive infusion. Three days later, his serotonin syndrome symptoms had disappeared completely.
UNASSIGNED: Findings in this case suggest that atomoxetine alone can cause serotonin syndrome presumably via its effects of serotonin reuptake inhibition. Clinicians should consider this syndrome induced by atomoxetine overdose.

Serotonin syndrome (SS) is a drug-induced clinical syndrome resulting from increased serotonergic activity in the central nervous system. Although more than seven decades have passed since the first description of SS, it is still an enigma in terms of terminology, clinical features, etiology, pathophysiology, diagnostic criteria, and therapeutic measures. The majority of SS cases have previously been reported by toxicology or psychiatry centers, particularly in people with mental illness. However, serotonergic medications are used for a variety of conditions other than mental illness. Serotonergic properties have been discovered in several new drugs, including over-the-counter medications. These days, cases are reported in non-toxicology centers, such as perioperative settings, neurology clinics, cardiology settings, gynecology settings, and pediatric clinics. Overdoses or poisonings of serotonergic agents constituted the majority of the cases observed in toxicology or psychiatry centers. Overdose or poisoning of serotonergic drugs is uncommon in other clinical settings. Patients may develop SS at therapeutic dosages. Moreover, these patients may continue to use serotonergic medications even if they develop mild to moderate SS due to several reasons. Thus, the clinical presentation (onset, severity, and clinical features) in such instances may not exactly match what toxicologists or psychiatrists observe in their respective settings. They produce considerable diversity in many aspects of SS. However, other experts discount these new developments in SS. Since SS is a potentially lethal illness, consensus is required on several concerns related to SS.