Calcium Carbonate as an Antacid for Oral Penicillin

Abstract
100,000 units of dry Ca penicillin combined with 2 g. of CaCO3 were given in gelatin capsules with water to fasting human subjects. Blood samples were drawn up to 4 hrs. later and the serum assayed for penicillin by the method of Rammelkamp. The serum levels were about twice as high as those following administration of 100,000 units of penicillin alone. The levels were also raised with penicillin-Na citrate mixts. They were lowered with mixts. of dry Na phosphate buffer, Al(OH)3, Mg(OH)2 or MgSiO3.