Antagonised effect on GI motility by anticholinergics, narcotic analgesics. Additive sedative effect w/ alcohol, sedatives, hypnotics, narcotics or tranquilizers. Diminished digoxin absorption. Increased acetaminophen, tetracycline, l-dopa, ethanol, cyclosporine rate &/or extent of absorption. Concomitant use w/ MAOIs. Tab: Incompatible w/ cephalothin Na, chloramphenicol Na, Na bicarbonate.