Increased effect w/ volatile agents eg, enflurane, isoflurane & halothane; ketamine; other non-depolarising neuromuscular blocking agents; antibiotics (including aminoglycosides, polymyxins, spectinomycin, tetracyclines, lincomycin & clindamycin); anti-arrhythmics (including propranolol, Ca channel blockers, lidocaine, procainamide & quinidine); diuretics (including furosemide & possibly thiazides, mannitol & acetazolamide); Mg salts; lithium salts; ganglion blocking drugs (trimetaphan, hexamethonium). Rarely, may aggravate or unmask latent myasthenia gravis or induce myasthenic syndrome w/ antibiotics, β-blockers (propranolol, oxprenolol), anti-arrhythmics (procainamide, quinidine), anti-rheumatics (chloroquine, D-penicillamine), trimetaphan, chlorpromazine, steroids, phenytoin & lithium. May prolong & complex block w/ suxamethonium. Decreased effect w/ phenytoin or carbamazepine. May shorten duration & diminish magnitude of neuromuscular blockade w/ donepezil.