What are the symptoms and treatment of a sertraline (selective serotonin reuptake inhibitor) overdose?

Sertraline Overdose: Side Effects and Management

Sertraline overdose typically causes mild to moderate symptoms including somnolence, vomiting, tachycardia, nausea, dizziness, agitation, and tremor, with serious toxicity being uncommon even at high doses. 1

Common Clinical Manifestations

The most frequently observed symptoms in sertraline overdose include:

• Somnolence and lethargy are the most common central nervous system effects 1, 2, 3
• Gastrointestinal symptoms including vomiting, nausea, and diarrhea occur frequently 1, 2
• Cardiovascular effects such as tachycardia are common, though bradycardia has been reported in isolated cases 1, 2
• Tremor and agitation represent neuromuscular manifestations 1, 3
• Dizziness is frequently reported 1

Serious but Less Common Complications

While most sertraline overdoses result in mild symptoms, potentially life-threatening complications can occur:

Serotonin Syndrome

• Serotonin syndrome is the most serious complication and can occur even with sertraline alone in massive overdoses 4, 5
• Key diagnostic features include: confusion/agitation (mental status changes), myoclonus/tremor/hyperreflexia/muscle rigidity (neuromuscular hyperactivity), and fever/tachycardia/sweating (autonomic instability) 6, 7, 4
• Symptoms typically emerge within 24-48 hours after ingestion or dose increases 6, 7
• Myoclonus occurs in 57% of cases and is the most common finding in serotonin syndrome 7

Cardiac and Neurological Complications

• QT-interval prolongation and Torsade de Pointes have been reported in overdose 1
• Seizures (convulsions) can occur in severe cases 1
• Coma, delirium, hallucinations, and stupor represent severe CNS depression 1
• Bundle branch block, hypertension, hypotension, and syncope are cardiovascular complications 1

Other Serious Effects

• Pancreatitis has been reported 1
• Manic reaction can occur 1
• Angioedema with airway compromise has been documented in combined overdoses, though this is rare 8

Dose-Related Toxicity

• The largest known single ingestion was 13.5 grams in a patient who recovered, though another patient died after ingesting only 2.5 grams, demonstrating variable individual susceptibility 1
• Mean overdose doses in case series range from 727 mg to 1,579 mg 2, 3
• In isolated sertraline overdoses of 52 patients, 34 remained asymptomatic and serious toxicity was not expected 2
• Deaths have been reported following very large ingestions, though the margin of safety is greater than for older antidepressants 6

Management Algorithm

Immediate Assessment

• Ensure adequate airway, oxygenation, and ventilation as the first priority 1
• Monitor cardiac rhythm and vital signs continuously 1
• Assess for serotonin syndrome using clinical criteria: look specifically for hyperreflexia, inducible clonus (especially ankle clonus), myoclonus, agitation, diaphoresis, and hyperthermia 7, 5

Gastrointestinal Decontamination

• Gastric lavage with a large-bore orogastric tube may be indicated if performed soon after ingestion or in symptomatic patients, with appropriate airway protection 1
• Activated charcoal should be administered 1
• Induction of emesis is NOT recommended 1

Specific Interventions

• If serotonin syndrome is suspected, immediately discontinue sertraline and all other serotonergic agents 7
• Administer benzodiazepines (such as lorazepam) for agitation, muscle rigidity, and seizures 7, 5
• Provide IV fluids for supportive care 7, 5
• External cooling measures for hyperthermia 7
• NEVER use physical restraints if serotonin syndrome is suspected, as they worsen muscle contractions and increase mortality risk 7

Ineffective Interventions

• Forced diuresis, dialysis, hemoperfusion, and exchange transfusion are unlikely to be beneficial due to sertraline's large volume of distribution 1
• No specific antidotes exist for sertraline overdose 1

Disposition and Monitoring

• Asymptomatic patients with isolated sertraline ingestion may be managed at home if the dose is small and the patient is reliable, particularly in children 2
• Symptomatic patients require ED observation with mean length of stay around 3.9 hours for those discharged 3
• Admission for 24-hour observation is warranted for significant ingestions or symptomatic patients 3
• Monitor for delayed presentations up to 24 hours post-ingestion, as serious reactions can develop over time 8

Critical Pitfalls to Avoid

• Do not dismiss patients with therapeutic-dose sertraline as incapable of developing serotonin syndrome—it can occur even at normal doses, particularly within the first three months of therapy 5
• Consider multiple drug involvement in all overdose cases, as benzodiazepines and alcohol are frequently co-ingested 1, 3
• Watch for unusual delayed presentations such as angioedema, which can develop hours after initial presentation 8
• Maintain high clinical suspicion for serotonin syndrome even when symptoms seem mild initially, as progression can occur 5