According to FDA prescribing information, the most severe reactions reported in trazodone overdose include priapism, respiratory arrest, seizures, ECG changes including QT prolongation, and SIADH (a cause of low blood sodium). The most frequently reported overdose reactions are drowsiness and vomiting. Combining trazodone with alcohol or other CNS depressants significantly raises the danger of an overdose.
If you suspect a trazodone overdose — your own or someone else's — call 911 immediately, or contact Poison Control at 1-800-222-1222 for guidance. Do not wait to see if symptoms improve on their own, and do not try to induce vomiting unless specifically instructed by Poison Control or emergency services.