Which SERM is associated with an increased risk of deep vein thrombosis?

• A. Raloxifene
• B. Tamoxifen
• C. Toremifene
• D. Ospemifene

Answer: (A)

Deep vein thrombosis risk with SERMs comes from their estrogen-like effects on coagulation pathways. Raloxifene, used for osteoporosis, reduces estrogen activity in breast and uterus but can still tilt the coagulation balance toward clot formation, so DVT and PE risk increases with its use. This is a well-documented adverse effect in studies of raloxifene, making it the SERM most classically associated with thromboembolic events among the options. The other SERMs have their own safety profiles: tamoxifen carries thromboembolism risk as well but adds endometrial cancer risk, ospemifene has less clear thrombotic risk data and is used for vaginal atrophy, and toremifene is associated with thromboembolism but is less emphasized in relation to DVT in typical exam contexts. Therefore, raloxifene is the best answer for the question about increased DVT risk.