<p>Increased risk of ECG abnormalities with quinine or chloroquine, antihistamines, TCAs and phenothiazines. May increase risk of seizure with quinidine or quinine. Concomitant use with valproic acid, phenobarbital, carbamazepine and phenytoin may cause loss of seizure control and lower plasma levels of anticonvulsants. Increased risk of QT prolongation and arrhythmia with ketoconazole. Concomitant use with digoxin, Ca channel blockers, antiarrhythmics and &beta;-blockers may increase the risk of cardiotoxicity. Increased risk of ventricular arrhythmias with amiodarone. Concomitant use with TCAs, SSRIs, buprion, antipsychotic, tramadol may increase the risk of convulsions. Increased plasma levels with metoclopromide. May compromise adequate immunisation by live typhoid vaccine. Vaccinations with attenuated live bacteria should be completed at least 3 days prior the 1st dose of mefloquine.</p>