(a) The active antacid ingredients of the product consist of one or more of the ingredients permitted in Sec. 331.11 within any maximum daily dosage limit established, each ingredient is included at a level that contributes at least 25 percent of the total acid neutralizing capacity of the product, and the finished product contains at least 5 meq of acid neutralizing capacity as measured by the procedure provided in the United States Pharmacopeia 23/National Formulary 18. The method established in Sec. 331.20 shall be used to determine the percent contribution of each antacid active ingredient.
(b) This section does not apply to an antacid ingredient specifically added as a corrective to prevent a laxative or constipating effect. [39 FR 19874, June 4, 1974, as amended at 61 FR 4822, Feb. 8, 1996]