1/6. serotonin syndrome induced by low-dose venlafaxine.OBJECTIVE: To report the case of a patient with serotonin syndrome induced by low-dose venlafaxine. CASE SUMMARY: A 29-year-old Taiwanese woman with major depressive disorder abruptly developed serotonin syndrome during low-dose (37.5 mg/d) venlafaxine monotherapy, with symptoms of restlessness, tremor, shivering, diarrhea, vomiting, ataxia, tachycardia, and myoclonus. The patient recovered in 2 hours after receiving prochlorperazine and lorazepam in the emergency department. Venlafaxine was discontinued, and she was discharged home. Two weeks later, the patient started to receive fluoxetine 20 mg/d and reported no adverse adverse effects during follow-up clinic visits. DISCUSSION: The clinical manifestations of this case meet Sternbach's criteria of serotonin syndrome. Its possible etiologic factors include panic attack, adverse drug reaction, pharmacodynamic interaction, and congenital absence of CYP2D6 enzyme activity. The Naranjo probability scale suggested a probable causality of venlafaxine treatment and serotonin syndrome. CONCLUSIONS: Clinicians should be aware of the risk of serotonin syndrome when the patient receives not only a combination of 2 antidepressants, but also the single potent serotonergic agent venlafaxine.- - - - - - - - - - ranking = 1keywords = probability (Clic here for more details about this article) |
2/6. serotonin syndrome with elevated paroxetine concentrations.OBJECTIVE: To describe a case of serotonin syndrome due to paroxetine and ethanol. CASE SUMMARY: A 57-year-old white man was brought to the emergency department one day after ingesting paroxetine 3600 mg and a pint of hard liquor. He denied the use of any other drug or herbal products and regular use of alcohol. Upon arrival to the hospital, vital signs were blood pressure 188/103 mm Hg, heart rate 114 beats/min, respiratory rate 28 breaths/min, temperature 36.8 degrees C, and O2 saturation 96% on room air. Findings on physical examination included dilated pupils, facial flushing, diaphoresis, shivering, myoclonic jerks, tremors, and hyperreflexia. A tentative diagnosis of serotonin syndrome was made. Initially, cyproheptadine 8 mg was administered orally with no observable effect. An additional 12 mg was given in 3 doses over 24 hours. Symptoms abated slowly over the next 6 days, during which a thorough evaluation failed to reveal any other potential causes for the patient's condition. serum paroxetine concentrations at 27.5 and 40 hours after ingestion were 1800 and 1600 ng/mL, respectively (normal 20-200 ng/mL). DISCUSSION: serotonin syndrome is rarely reported in patients taking only one serotonergic medication. Although serum paroxetine concentrations have not been shown to correlate with efficacy or toxicity, our patient's serum paroxetine concentration was 9 times the upper end of the therapeutic range. cyproheptadine, which has been suggested as a therapy, did not appear beneficial in this patient. Use of the Naranjo probability scale indicated a probable relationship between the serotonin syndrome and the overdose of paroxetine taken by this patient. CONCLUSIONS: More studies are needed to better assess the role of cyproheptadine and other serotonin antagonists in the management of the serotonin syndrome. Regardless of the use of cyproheptadine or other agents, attention should be paid to fluid status, decontamination, and management of hyperthermia, agitation, and seizures.- - - - - - - - - - ranking = 1keywords = probability (Clic here for more details about this article) |
3/6. Serotonin toxicity associated with concomitant use of linezolid.OBJECTIVE: To report 2 cases of serotonin toxicity (ST) associated with concomitant use of linezolid and serotonergic drugs and review previously published case reports. CASE SUMMARIES: Case 1. A 38-year-old white female with cystic fibrosis treated with venlafaxine 300 mg/day for one year was prescribed linezolid 600 mg intravenously every 12 hours for treatment of methicillin-resistant staphylococcus aureus (MRSA) pulmonary infection. She displayed symptoms of ST 8 days after the introduction of linezolid. The venlafaxine dosage was decreased to 150 mg/day, and symptoms gradually abated over 36 hours. Case 2. A 37-year-old male with multiple myeloma received citalopram 40 mg/day and trazodone 150 mg/day for anxiety-related disorders. Linezolid treatment with 600 mg orally twice daily was instituted for MRSA cellulitis. The following day, the patient developed anxiety, panic attacks, tremors, tachycardia, and hypertension that persisted throughout linezolid treatment. Symptoms finally waned 5 days after linezolid treatment was stopped. DISCUSSION: The symptoms observed in our patients were consistent with Sternbach's criteria for ST. A review of published case reports showed a short time to onset of symptoms following the introduction of linezolid, generally within 1-3 days. Also of note is the use of relatively high dosages of serotonergic drugs. Use of the Naranjo probability scale indicated a possible relationship between the use of linezolid and the occurrence of ST in both cases. CONCLUSIONS: Clinicians should pay special attention to patients treated with serotonergic drugs, especially those receiving dosages in the higher end of the normal range who are prescribed linezolid, and consider tapering or reducing the dosage of serotonergic drugs for the duration of antibiotic therapy.- - - - - - - - - - ranking = 1keywords = probability (Clic here for more details about this article) |
4/6. Antidepressant-induced adverse reactions in a patient with hemorrhagic stroke.OBJECTIVE: To report a case of antidepressant-induced adverse drug reactions in a patient with hemorrhagic stroke. CASE SUMMARY: A 56-year-old man developed life-threatening adverse reactions after fluoxetine was added to his previously prescribed regimen of buspirone and olanzapine. One week after starting fluoxetine 60 mg/day, the patient developed syndrome of inappropriate antidiuretic hormone secretion and serotonin syndrome concurrently. The patient had experienced a hemorrhagic stroke before the adverse drug reactions occurred. DISCUSSION: A patient with a history of hemorrhagic stroke developed serious adverse drug reactions when fluoxetine was added to his drug therapy. When the combination therapy was stopped, all adverse effects gradually disappeared and laboratory abnormalities were corrected. The likelihood that the adverse reactions were caused by fluoxetine is probable according to the Naranjo probability scale. In addition, a history of stroke may be a risk factor for the development of such reactions. CONCLUSIONS: Today, patients with depression after experiencing a stroke are treated more effectively, but antidepressant-induced adverse drug reactions may be serious. A growing number of patients are treated for post-stroke depression; they require close supervision and careful dosing of antidepressants to prevent full-blown adverse reactions from occurring.- - - - - - - - - - ranking = 1keywords = probability (Clic here for more details about this article) |
5/6. serotonin syndrome induced by fluvoxamine and oxycodone.OBJECTIVE: To report a case of severe serotonergic symptoms following the addition of oxycodone to fluvoxamine. CASE SUMMARY: A 70-year-old woman developed severe serotonergic features, including confusion, nausea, fever, clonus, hyperreflexia, hypertonia, shivering, and tachycardia, following the addition of oxycodone 40 mg twice daily to fluvoxamine 200 mg/day, easily fulfilling diagnostic criteria for serotonin syndrome. Discontinuation of the offending drugs resulted in resolution of her symptoms over 48 hours, and no other cause of the syndrome was identified. Use of the Naranjo probability scale indicated a probable relationship between the serotonergic symptoms and the addition of oxycodone to fluvoxamine therapy. DISCUSSION: serotonin syndrome is a serious adverse reaction usually due to interactions with serotonergic drugs. There have been only 3 previous reports involving oxycodone. Most previous reports of serotonin syndrome involving analgesics have been associated with meperidine, dextromethorphan, and tramadol. Unlike these synthetic opioids, however, oxycodone does not inhibit the reuptake of serotonin. In addition, there are a number of other possible pharmacologic mechanisms for the interaction we observed. CONCLUSIONS: Monitoring for serotonergic adverse events should be done when oxycodone is given to patients receiving serotonin-reuptake inhibitors.- - - - - - - - - - ranking = 1keywords = probability (Clic here for more details about this article) |
6/6. lithium and venlafaxine interaction: a case of serotonin syndrome.serotonin syndrome, which occurs as a result of enhanced serotonin concentration in the central nervous system, is a well-known adverse effect of serotonin-active medications. The concomitant use of antidepressant drugs associated with lithium as a co-adjuvant seems to increase the risk of this adverse reaction. We report a case of the serotonin syndrome during treatment with lithium and venlafaxine, an antidepressant with a dual selective re-uptake inhibition mechanism, and review the literature for similar cases. A 71-year-old woman developed serotonin syndrome while receiving treatment with moderate doses of lithium and venlafaxine for refractory depression. She had been taking higher doses of venlafaxine during the previous months with no significant secondary effects. Use of the Naranjo adverse drug reaction probability algorithm indicated a probable relationship between serotonin syndrome and treatment with lithium and venlafaxine.- - - - - - - - - - ranking = 1keywords = probability (Clic here for more details about this article) |