Ritonavir increases the AUC of 
trazodone by more than 2-fold and sedation and 
 fatigue were increased. Two cases of 
serotonin syndrome, have been reported in patients taking 
trazodone and 
ritonavir or indinavir. Other 
protease inhibitors may interact similarly. 
 A lower dose of 
trazodone should be considered if it is given with potent CYP3A4 
 inhibitors such as 
ritonavir and indinavir, although note that in the UK it has been 
 suggested that the combination should be avoided where possible.