In the latter case all H 2 RAs interact to a similar extent, as in reducing the oral absorption of ketoconazole. However, in the former two cases the available published data clearly indicate that, at equivalent therapeutic doses, cimetidine interacts to the greatest extent. However, the fact remains that patients may exceed the recommended dose, especially for heartburn. Also, patients with poor renal function, such as the elderly and diabetics, may eliminate H 2 RAs more slowly and will have high levels of active drug. Consider also that in general, the likelihood of clinically significant effects is low with many drug interactions of concern.
Pharmacists protect patients from adverse outcomes such as avoiding potential drug interactions.
It is clear that cimetidine is the H 2 RA with the greatest potential to interact with certain drugs, including some that have a narrow therapeutic range. E.M. Hawes, Ph.D. Professor of Pharmacy College of Pharmacy and Nutrition University of Saskatchewan Saskatoon, Saskatchewan A faithful reader I must tell you that I think your publication is an excellent one, which I enjoy reading every month. It provides a wonderful continuing education resource. Unfortunately, the source for your information on Drug Information Centres is incomplete. Our DI centre is alive and well but was not included in the list of DI centres in Ontario.