Serious reactions w/ irreversible, nonselective MAOIs. Risk of serotonin syndrome w/ reversible, selective MAO-A inhibitor (eg, moclobemide); reversible, nonselective MAOI (eg, linezolid); irreversible, selective MAO-B inhibitor (eg, selegiline). Class IA & III antiarrhythmics, antipsychotics (eg, phenothiazine derivatives, pimozide, haloperidol), TCAs, antimicrobial agents (eg, sparfloxacin, moxifloxacin, erythromycin IV, pentamidine, halofantrine), certain antihistamines (eg, astemizole, mizolastine). May lead to serotonin syndrome w/ serotonergic drugs eg, tramadol, sumatriptan & other triptans. Medicinal products capable of lowering seizure threshold eg, antidepressants (tricyclics, SSRIs), neuroleptics (phenothiazines, thioxanthenes, butyrophenones), mefloquine, bupropion & tramadol. Enhanced effects w/ lithium or tryptophan. Increased incidence of adverse events w/ St. John's wort-containing prep. Altered anticoagulant effects. Increased bleeding tendency w/ NSAIDs. Alcohol. Concomitant use w/ hypokalaemia/hypomagnesaemia inducing medicinal products.