Cimetidine increases the AUC and peak 
plasma levels of 
mirtazapine by 54% and 22%, 
 respectively. 
Mirtazapine does not appear to affect the 
pharmacokinetics of 
cimetidine. 
 The manufacturers advise that the 
mirtazapine dosage may need to be reduced during concurrent use and increased if 
cimetidine is stopped. Monitor for an increase in adverse effects when starting 
cimetidine.