Toxic and sometimes fatal reactions (similar to or the same as serotonin 
syndrome) have very occasionally occurred in patients taking both 
MAOIs and tricyclic 
 antidepressants. A case report suggests that 
trazodone may interact similarly.  
Trazodone should not be started for 2 weeks after treatment with 
MAOIs has been stopped, and an MAOI should not be started until 1 week after 
trazodone has been stopped. If concurrent use is thought necessary it has been suggested that it should only be undertaken by those well aware of the problems and who can undertake adequate supervision. The US manufacturers suggest starting at low doses, and increasing cautiously.