About Trazodone Serotonin Reuptake Inhibitor/Antagonist, a triazolopyridine derivative, Antidepressant. Mechanism of Action of Trazodone Trazodone has prominent 5HT2 antagonistic action and alpha adrenergic blocking action. It selectively but less efficiently blocks the re-uptake of neurotransmitter Serotonin from the synapse in to the presynaptic nerve terminal in the CNS. Trazodone potentiates the neurotransmitter activity and produces antidepressant action. It also produces sedation. Indications for Trazodone 1. Depression. Interactions for Trazodone Alcohol, Barbiturates and other CNS depressants : Trazodone enhances the CNS depressant effects of these drugs. Digoxin : Serum levels of digoxin increased. MAOIs : Exercise caution when coadministering trazodone. Phenytion : Increased serum levels of phenytoin. Warfarin: The hypoprothrombinemic effect of warfarin may be decreased.