SPL Set ID: 7d550b12-065a-416c-93fa-b61368eeb36f

Disopyramide phosphate is an antiarrhythmic drug available for oral administration in immediate-release capsules containing 100 mg or 150 mg of disopyramide base, present as the phosphate. The base content of the phosphate salt is 77.6%. The structural formula of disopyramide phosphate is: C 21 H 29 N 3 O∙H 3 PO 4 M.W. 437.47 (±)-α-[2-(Diisopropylamino)ethyl]-α-phenyl-2-pyridineacetamide phosphate (1:1). Disopyramide phosphate is freely soluble in water, and the free base (pKa 10.4) has an aqueous solubility of 1 mg/mL. The chloroform: water partition coefficient of the base is 3.1 at pH 7.2. Disopyramide phosphate is a racemic mixture of d - and l -isomers. This drug is not chemically related to other antiarrhythmic drugs. Disopyramide phosphate capsules (equivalent to 100 mg Disopyramide Base) and Disopyramide phosphate capsules (equivalent to 150 mg Disopyramide Base) contain the following inactive ingredients: magnesium stearate, microcrystalline cellulose and sodium lauryl sulfate. The capsule shells contain gelatin, methylparaben, propylparaben, and titanium dioxide. The 100 mg capsule shell also contains D&C Red No. 28, D&C Yellow No. 10, FD&C Blue No. 1 and FD&C Red No. 40. The 150 mg capsule shell also contains black iron oxide and red iron oxide. Chemical Structure