Dextromethorphan: Tricyclic antidepressants (TCAs), antipsychotics, anxiolytics and hypnotics, cimetidine, ciprofloxacin, domperidone, metoclopramide, mexiletine, CYP2D6 inhibitors, ritonavir, alcohol.
Potentially Fatal: Memantine, moclobemide.
Triprolidine + Pseudoephedrine: Increased BP with other sympathomimetic agents (e.g. decongestants, TCA, appetite suppressants). Reduced hypotensive effects of methyldopa, ?- and ?-adrenergic blockers. Increased side effects (e.g. somnolence, agitation) with atomoxetine.
Potentially Fatal: Increased risk of hypertensive crisis with furazolidine, avoid concurrent use. Increased risk of hypertensive crisis with MAOIs; avoid concurrent use or within 2 wk after stopping MAOIs. Increased risk of psychosis with bromocriptine.