Rhea Vitamin B Complex + C Drug Interactions

Pyridoxine Hydrochloride (B6): Effects of levodopa are reduced with administration of vitamin B6, but it does not occur if a dopa decarboxylase inhibitor is also given. Vitamin B6 reduces the activity of altretamine. It has also been reported to decrease serum concentrations of phenobarbital. Many drugs increase the requirements for vitamin B6 such as hydralazine, isoniazid, penicillamine and oral contraceptives.
Cyanocobalamin (B12): Absorption of vitamin B12 from the gastrointestinal tract may be reduced by neomycin, aminosalicylic acid, histamine H2-antagonist, omeprazole, and colchicine. Vitamin B12 serum concentrations may be decreased by use of oral contraceptives. Parenteral chloramphenicol may attenuate the effect of vitamin B12 in anemia.
Ascorbic Acid: It should not be given for the first month after starting desferrioxamine treatment. Giving ascorbic acid for vitamin C deficiency to patient receiving fluphenazine for bipolar disorder was associated with decreased in serum concentrations of fluphenazine and deterioration of behavior. Omeprazole may affect the bioavailability of dietary vitamin C.