Drug Interactions in Prescriptions for Outpatients

Drug interactions were found in 925 (6.3%) out of 14, 575 prescriptions for outpatients filled in three months from November 1, 1976, to January 31, 1977, at Akita University Hospital. The 925 prescriptions included not a serious incompatibility but 59 prescriptions (16.3%) which turned out to have directed improper combinations and 302 (83.7%) directing combinations requiring precautions. It was found out that doctors, under agreement with prescribing physicians, were apt to administer two or more drugs concurrently without confirming the ingredients of the compounds. Even when adverse reactions occurred, the physicians were compelled to use drugs weighing beneficial effect against untoward effect, though they were aware of the interactions they carried out concurrent use of drugs expecting beneficial interactions. In order to prevent serious adverse reactions due to the drug interactions, pharmacists should keep constant communication with physicians so as to examine the drugs before they are ditributed to the patients.