Raloxifene

Key facts

• Raloxifene (sold as Evista) is a selective estrogen receptor modulator. It mimics estrogen's protective effect on bone while blocking estrogen's action in breast tissue.
• You take one tablet daily, with or without food; benefits on bone density build up over months to years of continuous use.
• Raloxifene increases the risk of venous blood clots (deep vein thrombosis, pulmonary embolism) and of fatal stroke; this is a boxed warning on the medicine's label.
• Seek urgent care for leg swelling or pain, sudden shortness of breath or chest pain, or sudden weakness, confusion, or trouble speaking.

What raloxifene treats

Raloxifene treats and helps prevent osteoporosis in postmenopausal women, reducing the risk of spinal fractures. It is also used to reduce the risk of invasive breast cancer in postmenopausal women who have osteoporosis or another risk factor for the disease. It does not treat menopausal hot flushes and can make them worse.

How raloxifene works

Estrogen receptors sit in tissues throughout the body, including bone, breast, and the uterus. Raloxifene attaches to these receptors and behaves like estrogen in bone, slowing the breakdown that leads to fracture, while blocking estrogen's effect in breast tissue, which is why it can lower breast cancer risk instead of raising it.

Before you take it

• Do not take raloxifene if you have had a venous blood clot (DVT, pulmonary embolism, or retinal vein thrombosis), or if you could become pregnant; it is not for use before menopause.
• Tell your prescriber about a history of stroke, atrial fibrillation, or other conditions that raise clotting risk.
• Stop raloxifene at least 3 days before planned surgery or any period of prolonged immobility, such as long-haul travel, and do not restart until you are fully mobile again.
• Mention other medicines you take, including estrogen therapy, cholestyramine, and anticoagulants such as warfarin.

Side effects

Common effects include hot flushes, leg cramps, joint pain, sweating, and mild swelling of the hands or feet.

Stop and seek urgent medical care for any of these:

• Swelling, pain, warmth, or redness in one leg.
• Sudden shortness of breath, chest pain, or coughing up blood.
• Sudden weakness or numbness on one side, trouble speaking, or facial drooping.
• Sudden vision changes.

Safety essentials

• Raloxifene raises the risk of dangerous blood clots and fatal stroke; this risk rises further with immobility, so plan ahead of surgery or long trips and stop the medicine beforehand as your prescriber advises.
• Do not use it if you have ever had a blood clot in a vein; this history rules it out.
• Report leg swelling, sudden breathlessness, or stroke-type symptoms immediately rather than waiting to see if they pass.

This page is educational and does not replace advice from a doctor or pharmacist who knows your health history.