OBJECTIVE: To determine whether prescription prenatal vitamins meet United States Pharmacopeial Convention (USP) standards for folic acid dissolution. METHODS: Dissolution was measured using USP Apparatus II and test conditions specified in the 23rd revision of the United States Pharmacopeia (USP 23). Folic acid was assayed by a chromatographic method modified from that specified in the official monographs, for oil- and water-soluble vitamins with minerals tablets, in USP 23. RESULTS: Only three out of nine multivitamin products met USP specifications for folic acid release. Most missed by a wide margin; folic acid dissolution from two products was less than 25%. CONCLUSIONS: Because a wide variety of brand-name and generic prescription prenatal multivitamin products were tested, these results are likely to be representative of the multivitamin products on the market. Given the significance of folic acid to public health, the authors believe that this subject should be studied further and that prompt action should be taken to ensure that folic-acid-containing products are of the highest quality possible.

Chemistry, Pharmaceutical↗

PubMedDate not supplied

Factors to consider in the selection of a calcium supplement.

Calcium supplements are widely used, yet many questions remain as to the absorption of various calcium salts. Because the solubility of many calcium salts is dependent upon pH, the type of salt used, the condition of the patient, and the time of administration should be considered. Studies show that many calcium supplements on the market today do not meet standards of quality established in the "U.S. Pharmacopeia" (USP). Consumers must be discerning about the products they purchase. Calcium supplements should be taken with meals to ensure solubility. Calcium carbonate, and particularly tribasic calcium phosphate tablets, are not recommended for patients with achlorhydria. Calcium tablets, like almost all drugs, should be taken with 8 ounces of water or other liquid.

Calcium↗