Toremifene citrate

About Toremifene citrate

Toremifene citrate is an anti-estrogenic medicine classified as a selective estrogen receptor modulator (SERM) with mixed agonist and antagonist properties. The substance is a non-steroidal triphenylethylene derivative and is similar in structure and effect to the drugs Nolvadex (tamoxifen citrate) and Clomid (clomiphene citrate). Toremifene citrate is used to treat breast cancer in post-menopausal women with estrogen-positive or indeterminate tumours (i.e. if it is not certain whether the cancer is estrogen responsive). The drug works by competitive attachment to estrogen receptors in various tissues, blocking the biological activity of endogenous estrogen. In men (bodybuilders and athletes) toremifene citrate is used as an anti-estrogen for many tissues. The substance counteracts some of the side effects associated with the use of aromatizing or estrogenic anabolic/androgenic steroids, including gynecomastia, increased fat accumulation and water retention. Triphenylethylene compounds (toremifene citrate, tamoxifen citrate, clomiphene citrate) generally show some estrogenic activity in the liver. This means that these substances may simultaneously block oestrogenic activity in some body organs and act as oestrogens in other key areas. In the liver, estrogens play an important role in regulating serum cholesterol levels (the drug supports HDL synthesis and reduces LDL levels). Since bodybuilders using steroids often experience adverse cardiovascular effects, they are not recommended to use aromatase inhibitors (which reduce total serum estrogen levels). For such athletes, a product that blocks gynaecomastia and at the same time maintains optimal cholesterol values would be suitable. Trifenylethylene is the most effective drug in this regard, and evidence suggests that positive changes in lipid levels are significantly stronger with toremifene than with tamoxifen. Toremifene citrate may therefore be the preferred anti-estrogen for users interested in maintaining their lipid profile.

History

In 1997, Toremifene citrate was approved by the FDA as a prescription drug. The drug is marketed in the US under the brand name Fareston from GTx, Inc Fareston, and is also available in more than two dozen other countries such as Australia, Austria, Belgium, Czech Republic, Finland, France, Germany, Greece, Hungary, Ireland, Italy, Mexico, Netherlands, New Zealand, Portugal, Russia, South Africa, Spain, Sweden, Switzerland, Thailand, Turkey and UK.

Structural characteristics

Toremifene citrate is classified as a selective estrogen receptor modulator, exhibiting both agonist and antagonist properties.

Side effects

Toremifene citrate is well tolerated by most patients and the incidence of serious side effects when taken is considered fairly low. In clinical trials, common side effects associated with the use of Toremifene included: hot flushes (35%), sweating (20%), increased liver enzyme activity (19%), nausea (14%), vaginal discharge (13%), dizziness (95%), swelling (5%), vomiting (4%) and vaginal bleeding (2%). Other observed rare adverse effects that may be associated with the use of toremifene citrate include: decreased white blood cell and platelet counts, skin discoloration or dermatitis, constipation, difficulty breathing, partial motor paralysis, tremor, dizziness, pruritus, anorexia, visual disturbances, loss of strength, hair loss, depression, jaundice and muscle stiffness. Use of anti-estrogens may be harmful to the developing fetus, and women should avoid their use during pregnancy.

Use

Toremifene citrate is FDA approved for the treatment of metastatic breast cancer in postmenopausal women with estrogen-positive or unknown tumours. The recommended dose is one 60 mg tablet once daily. When used (off-label) to mitigate the estrogenic side effects of anabolic/androgenic steroids, men (athletes and bodybuilders) may use the drug at a dose of 30 mg to 60 mg daily while taking steroids.