Trazodone can make driving or handling other dangerous machinery more hazardous, particularly during first few days oftreatment, and further impairment may occur with alcohol.
Clinical evidence,mechanism, importance and management
A study in 6 healthy subjects comparing effects of single-doses of amitriptyline 50mg and trazodone 100mg found that both drugs impaired performance of a number of psychomotor tests, causing drowsiness and reducing clearheadedness to approximately same extent. Only manual dexterity was further impaired when subjects taking trazodone were given sufficient alcohol to give blood levels of about 40 mg% (See reference number 1).
Another study similarly found that impairment of psychomotor performance by trazodone was increased by alcohol.(See reference number 2) This appears to be due to a simple additive depression of CNS. This is an established interaction,and of practical importance. Patients should be warned that their ability to drive,handle dangerous machinery or to do other tasks needing complex psychomotor skills might be impaired by trazodone, and further worsened by alcohol.
Warrington SJ,Ankier SI, Turner P. Evaluation of possible interactions between ethanol andtrazodone or amitriptyline. Neuropsychobiology (1986) 15 (Suppl 1), 31–7.
Tiller JWG. Antidepressants,alcohol and psychomotor performance. Acta Psychiatr Scand (1990) (Suppl 360), 13–17.