Habit, prejudice, power and politics: issues in the conversion of H2-receptor antagonists to over-the-counter use.

H2-receptor antagonists have been widely prescribed in the last 20 years and are considered to rank among the safest drugs known. In several countries they have been switched to over-the-counter (OTC) status, and a similar move is under consideration in Canada. Some concerns have been raised as to the effectiveness of these drugs in the treatment of dyspepsia and heartburn, their safety when taken for self-diagnosed symptoms, and the potential for their use to delay diagnosis or mask serious disease. The author presents evidence to support the use of OTC H2-receptor antagonists in the treatment of dyspepsia. He argues that the safety record of these drugs is reassuring and that they are unlikely to mask gastric cancer. Finally, he describes the appropriate place of OTC H2-receptor antagonists in the overall management of acid-related disorders.