Prevention of adverse drug interactions.

1 The awareness and recognition of adverse interactions between drugs by prescribers is low. 2 A 6-month prospective study on patients on long-term outpatient anticoagulant therapy in the Grampian area has been carried out to evaluate a simple and cheap warning system. 3 The practitioners of patients in the test group were issued with warning labels which showed drugs known to interact. A reduction in the initiation of prescriptions for potentially interacting drugs was shown between the test and control groups (no warning labels). 4 The 140 practitioners who completed the study found the system to be convenient and useful. Extension to other high-risk drugs with the potential to interact with other drugs is planned. This system has the advantage of being drug and patient-orientated whereas lists of drug interactions or drug discs require more conscious effort by the prescriber.