Why don I see more adverse outcomes in patients receiving interacting drug combinations?
This is one of the most perplexing questions about drug interactions, and one that causes considerable confusion among health care providers. Patients frequently receive interacting drugs without developing adverse consequences,14 leading to questions regarding whether particular drug interactions are clinically important. In some cases, the lack of adverse consequences is simply because the 2 drugs do not actually interact, and they have been put on the computerized drug interaction screening system in error. In other cases, however, the 2 drugs can interact to produce adverse outcomes, but the patient in question does not have the pertinent risk factors for this interaction and/or the drugs were not given in such a way that an adverse outcome occurred. Broadly speaking, drug interactions can be divided into 3 categories: type A, type B, and type C. Type A. Drug interactions that produce adverse outcomes in most patients. These interactions are usually easy for the pharmacist to handl
