What are the adverse side effects of selective estrogen receptor modulators?
Just as estrogen has effects on multiple organ systems and target tissues, the effects of selective estrogen receptor modulators (SERMs) are broad. SERMs, including tamoxifen and raloxifene, are a group of structurally diverse compounds with both agonistic and antagonistic estrogen effects. Venous thromboembolism. Raloxifene produces up to a three-fold increase in the relative risk of venous thromboembolism events (VTE), including deep vein thrombosis, pulmonary embolism, and retinal vein thrombosis (1-4), similar to the risk seen with estrogen and tamoxifen therapy. The risk is highest in the first year of therapy. The number needed to treat (NNT) over a 3 year period to cause one additional VTE event is 170 (2). Although the relative risk decreases over time, there is an increased risk with continued therapy. On this basis, raloxifene is contraindicated in patients with a history of venous thromboembolism. In addition, patients should discontinue raloxifene 3 days prior to and during
