Chewable tab/syr/oral drops: Ascorbic acid: May induce tissue desaturation w/ aspirin, nicotine, appetite suppressant, Fe, phenytoin, anticonvulsant drugs, estrogen-containing OCs & tetracycline. May decrease plasma conc of fluphenazine. Reduced absorption & decrease urinary excretion w/ aspirin. May increase urinary Al elimination. Lower serum levels w/ OCs. Zn sulfate monohydrate: May inhibit absorption of copper. May reduce absorption of tetracyclines & quinolones (eg, ciprofloxacin, levofloxacin, moxifloxacin, norfloxacin & ofloxacin). Absorption may be reduced by Ca salts, oral Fe, penicillamine & trientine.