Sulfite content of drug products

A survey of drug manufacturers was conducted to identify drug products containing sulfiting agents; the list compiled of such products is presented in this paper. Letters were sent to the 224 manufacturers listed in the 1984 Physicians' Desk Reference requesting a list of all products containing sulfiting agents. A follow-up letter was sent to manufacturers who did not respond within three months. Of those manufacturers surveyed, 153 (68%) responded adequately; 71 (32%) did not respond or provided inadequate information. Some of the manufacturers referred the inquiry to parent companies, subsidiaries, or suppliers; 34 of these responded. A total of 187 manufacturers supplied a list of sulfite-containing drug products or stated that they did not produce any. Sulfites are present in a substantial number of drug products.