Stability of Iodine Solutions and Tinctures*†‡

Storage experiments on Iodine Tincture U. S. P., Strong Iodine Tincture N. F., Solution of Iodine N. F., and Strong Solution of Iodine U. S. P. have been carried out over a period of thirty months. These preparations were found to be stable in clear, amber, and blue glass‐stoppered bottles. Additional studies on Iodine Tincture when in actual use in first‐aid cabinets for a period of a year showed that this preparation maintained the required Pharmacopœia strength. Assay of collected samples of Strong Iodine Tincture which had been subject to household use for indefinite periods indicate that improperly stored samples of this product may have an iodine content higher than that permitted by the official compendia.