Interaction between Warfarin and Exenatide of One Diabetic Patient Complicated with Atrial Fibrillation / 中国药学杂志

ABSTRACT

OBJECTIVE: Blood tends to deposit in atrium to form thrombus in patients with atrial fibrillation. Patients with diabetes are in high coagulation state, for whom thrombosis is easy to occur. The number of diabetic patients with atrial fibrillation is large. Warfarin is one of the most widely used oral anticoagulants, which can cause major or fatal bleeding, so it is necessary to perform regular monitoring of international normalized ratio (INR) on all patients treated with warfarin. New kinds of antidiabetic drugs are widely used in clinic, among which a lot affect INR levels achieved with warfarin therapy. Clinical pharmacists should pay attention to drug interactions and monitor adverse drug reactions. As a new antidiabetic drug, exenatide has less reports of interaction with warfarin. The characteristic of the interaction between exenatide and warfarin was investigated, with the aim to optimize the rational and individualized medication. METHODS: A case was introduced in which exenatide was administrated combined with warfarin, so that the possible mechanism of exenatide affecting to warfarin were analyzed. RESULTS: INR declined from 2.13 to 1.57 after exenatide being added, and decreased further to 1.43 with concurrency of the increasing exenatide dose. On the contrary, INR was on rise as result of discontinuing exenatide. At last, INR returned to 1.78 when the patient discharged. CONCLUSION: Exenatide inhibited the absorption of warfarin, which lead to INR decline attributed to its effect of slowing down the gastric emptying. When exenatide and warfarin are combined, the dose of warfarin must be adjusted based on INR under clinical monitoring.