Drug Interaction Report

MONITOR CLOSELY: There are no clinical data on the use of tranexamic acid in combination with estrogens or selective estrogen receptor modulators. Because tranexamic acid is an antifibrinolytic agent, concomitant use may further exacerbate the risk of thrombotic events, including venous thromboembolism as well as arterial thromboses such as stroke and myocardial infarction, associated with estrogenic therapy. During postmarketing use of tranexamic acid for the treatment of cyclic heavy menstrual bleeding, there have been reports of venous and arterial thrombotic events in women who used tranexamic acid during treatment with combination hormonal contraceptives.

MANAGEMENT: Caution and close monitoring for thromboembolic adverse effects are recommended if tranexamic acid is prescribed with estrogens or selective estrogen receptor modulators. Patients should be advised to seek medical attention immediately if they experience potential signs and symptoms of blood clots such as chest pain, shortness of breath, hemoptysis, hematuria, sudden loss of vision, and pain, redness or swelling in an extremity.

ADJUST DOSING INTERVAL: Food significantly enhances the oral bioavailability of ospemifene. In a cross-study comparison, administration of a single 60 mg dose of ospemifene with a high-fat/high-calorie meal (860 kcal) in postmenopausal women increased ospemifene peak plasma concentration (Cmax) and systemic exposure (AUC) by 2.3- and 1.7-fold, respectively, compared to administration under fasted condition. Elimination half-life and time to maximum concentration (Tmax) were not altered. In two separate food effect studies where different ospemifene tablet formulations were given to healthy male volunteers, ospemifene Cmax and AUC increased by 2.3- and 1.8-fold, respectively, with a low-fat/low-calorie meal (300 kcal) and 3.6- and 2.7-fold, respectively, with a high-fat/high-calorie meal (860 kcal) relative to fasting.

MANAGEMENT: Ospemifene should be taken once daily with food.