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Predicting serotonin toxicity in serotonin reuptake inhibitor overdose
Joyce Cooper1,2, Stephen B Duffull3, Geoffrey K Isbister1,4
1Clinical Toxicology Research Group, University of Newcastle, Townsville, Australia.
Clinical Toxicology (Philadelphia, Pa.)
|November 29, 2022
Summary
Serotonin toxicity is common after antidepressant overdose, with risk significantly increased by moclobemide and decreased by olanzapine or risperidone. Dose plays a minor role in toxicity probability.
Area of Science:
- Pharmacology
- Toxicology
- Clinical Medicine
Background:
- Selective serotonin reuptake inhibitors (SSRIs) and serotonin norepinephrine reuptake inhibitors (SNRIs) are widely prescribed antidepressants.
- Overdose of these agents can lead to serotonin toxicity, a potentially life-threatening condition.
- Understanding the factors influencing serotonin toxicity is crucial for effective clinical management.
Purpose of the Study:
- To determine the frequency of serotonin toxicity after overdoses involving SSRIs and SNRIs.
- To identify factors that influence the probability of developing serotonin toxicity.
Main Methods:
- Retrospective cohort study of 1978 overdoses over 23 years.
- Inclusion of selective serotonin reuptake inhibitors (SSRIs) and serotonin norepinephrine reuptake inhibitors (SNRIs).
- Multivariate mixed effects logistic regression analysis to identify influencing factors.
Main Results:
- Serotonin toxicity occurred in 13.6% of overdoses.
- Increased probability of toxicity with higher doses (slight effect) and SNRI vs. SSRI.
- Markedly increased risk with moclobemide co-ingestion; significantly reduced risk with olanzapine or risperidone co-ingestion.
Conclusions:
- Serotonin toxicity is a frequent complication of SSRI/SNRI overdose.
- Co-ingestion with specific agents (moclobemide, olanzapine, risperidone) significantly alters toxicity risk.
- While dose influences risk, its effect is less pronounced than that of co-ingested substances.
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