Tibolone

Tibolone.svg

Synthetic steroid used in hormone replacement therapy

Tibolone
Trade names	Livial, Tibofem, others
Chemical nomenclature
IUPAC name	(7R,8R,13S,14S,17S)-17-ethynyl-7,13-dimethyl-6,7,8,9,11,12,14,15,16,17-decahydrocyclopenta[a]phenanthren-3-one
Routes	Oral
Metabolism	Hepatic
Identifiers
CAS Number	5630-53-5
PubChem	656659
DrugBank	DB09070
ChemSpider	571054
UNII	0KJ3YX6F1O
KEGG	D08578
ChEMBL	1201320
Chemical data
Chemical formula	C_21H_28O_2
Molecular weight	312.45

Tibolone is a synthetic steroid used primarily in hormone replacement therapy (HRT) for postmenopausal women. It is marketed under various brand names, including Livial and Tibofem. Tibolone exhibits tissue-specific effects, acting as an estrogen, progestogen, and androgen depending on the target tissue.

Pharmacology

Tibolone is metabolized into three active metabolites that contribute to its tissue-specific effects. These metabolites include:

• 3α-hydroxytibolone
• 3β-hydroxytibolone
• Δ4-tibolone

The metabolites exhibit varying affinities for estrogen, progesterone, and androgen receptors, which allows tibolone to mimic the effects of these hormones in different tissues.

Medical Uses

Tibolone is primarily used for the treatment of symptoms associated with menopause, such as hot flashes, vaginal atrophy, and osteoporosis. It is also used to prevent postmenopausal osteoporosis.

Menopausal Symptoms

Tibolone is effective in alleviating common menopausal symptoms, including hot flashes and night sweats. It also helps in maintaining vaginal health by reducing vaginal dryness and atrophy.

Osteoporosis

Tibolone has been shown to have a positive effect on bone mineral density, making it a useful option for the prevention and treatment of osteoporosis in postmenopausal women.

Side Effects

Common side effects of tibolone include:

• Breast tenderness
• Weight gain
• Abdominal pain
• Vaginal bleeding

Serious side effects may include an increased risk of breast cancer, stroke, and cardiovascular disease.

Contraindications

Tibolone is contraindicated in individuals with:

• Breast cancer
• Endometrial cancer
• Liver disease
• Thromboembolic disorders

Mechanism of Action

Tibolone's mechanism of action involves its conversion into active metabolites that interact with estrogen, progesterone, and androgen receptors. This interaction results in tissue-specific effects that help alleviate menopausal symptoms and prevent osteoporosis.

History

Tibolone was developed in the 1960s and has been used in clinical practice since the 1980s. It is available in many countries worldwide and is commonly prescribed for hormone replacement therapy in postmenopausal women.

See Also

• Hormone replacement therapy
• Menopause
• Osteoporosis
• Estrogen
• Progestogen
• Androgen