Raloxifene

What is Raloxifene?

Raloxifene, sold under the brand name Evista, is a medication classified as a Selective Estrogen Receptor Modulator (SERM). SERMs are a type of drug that acts on the estrogen receptor. The "selective" part is key: Raloxifene acts like estrogen in some tissues (agonist) and blocks estrogen in others (antagonist).

• In bones and the liver: It acts as an estrogen agonist, helping to prevent bone loss and lower LDL ("bad") cholesterol.

• In breast and uterine tissue: It acts as an estrogen antagonist, blocking estrogen's effects and thus helping to prevent certain types of breast cancer.

Other names for Raloxifene include:

• Evista (brand name)

• Keoxifene

• Pharoxifene

• LY-139481

• LY-156758

Side Effects and Benefits

Benefits:

• Prevention and treatment of osteoporosis: Raloxifene helps strengthen bones and reduces the risk of fractures, particularly in the spine, in postmenopausal women.

• Reduction of breast cancer risk: It is used to lower the risk of invasive breast cancer in postmenopausal women who are at high risk for the disease.

Side Effects:

• Common side effects: Hot flashes, leg cramps, swelling of the hands, feet, or ankles, and joint pain. These are often most common in the first six months of treatment.

• Serious side effects: The most significant and serious risk associated with Raloxifene is the increased risk of blood clots. This includes deep vein thrombosis (DVT), pulmonary embolism (PE), and retinal vein thrombosis. It can also increase the risk of a serious or fatal stroke in women with a history of coronary artery disease.

Pros and Cons

Pros:

• Dual benefit: It treats osteoporosis and reduces the risk of invasive breast cancer.

• No increased risk of uterine or breast cancer: Unlike some other hormone therapies, Raloxifene does not stimulate the uterus, so it does not increase the risk of endometrial cancer. In fact, it can lower the risk of certain types of estrogen-fueled breast cancer.

• Convenient dosage: It is a once-daily tablet.

Cons:

• Risk of blood clots: The most serious con is the increased risk of life-threatening blood clots.

• May not be as effective for osteoporosis as other drugs: For osteoporosis alone, Raloxifene may be less potent than bisphosphonates.

• Can cause hot flashes: It may not alleviate menopausal symptoms like hot flashes and can even cause them.

• Not suitable for everyone: It is not for men, premenopausal women, or those with a history of blood clots.

Dosage and Frequency

The standard recommended dosage of Raloxifene is 60 mg taken once daily. It can be taken at any time of day, with or without food. For the prevention of osteoporosis and reduction of breast cancer risk, it is often prescribed for long-term use, potentially for several years.

Half-Life and Detection Time

• Half-life: The elimination half-life of Raloxifene is approximately 27.7 hours after a single oral dose. This can be prolonged due to its enterohepatic cycling.

• Detection time: Raloxifene is a substance on the World Anti-Doping Agency (WADA) Prohibited List. For doping analysis, it can be detected in urine. Studies have shown that it can be detectable for 6 to 10 days or more after a single dose.

Sterogenic, Progestronic, and Prolactin Effects

• Sterogenic/Estrogenic: As a SERM, Raloxifene's effects are complex. It is estrogenic in some tissues (bone) and anti-estrogenic in others (breast and uterus).

• Progestronic: Raloxifene does not have progestogenic effects.

• Prolactin: Raloxifene has been shown to decrease serum prolactin levels in postmenopausal women, which can be a therapeutic benefit for those with hyperprolactinemia.