Selective Estrogen Receptor Modulators (SERMs)

Tamoxifen

• Mechanism
  • estrogen antagonist in breast
  • estrogen agonist in endometrium, bone
• Indications
  • estrogen-receptor positive breast cancer
• Toxicity
  • ↑ risk of DVTs
  • ↑ risk of endometrial cancer 
    • secondary to agonist activity
  • induces menopause
    • hot flashes
  • prevents osteoporosis
• secondary to agonist action in bone

Raloxifene

• Mechanism 
  • estrogen antagonist in breast
  • estrogen agonist in bone
• Indications
  • osteoporosis in menopausal women
• Toxicity
  • ↑ risk of DVTs
  • induces menopause
    • hot flashes
  • NO ↑ risk of endometrial cancer
    • secondary to antagonist activity in endometrium