Composition, release form and packaging
Tablets – 1 tablet:
- Active substance: tamoxifen citrate 30.4 mg, which corresponds to the content of tamoxifen 20 mg.
- Excipients: lactose monohydrate – 142.6 mg, sodium starch glycolate – 20 mg, povidone – 5 mg, microcrystalline cellulose – 49.6 mg, magnesium stearate – 2.4 mg.
- Shell composition: white opadry dye – 5 mg (lactose – 1.8 mg, titanium dioxide – 1.3 mg, hypromellose – 1.4 mg, polyethylene glycol 4000 – 0.5 mg).
10 pcs. – contour cellular packaging (3) – cardboard packs.
Description of dosage form
Coated tablets; white or slightly yellowish in color, round, biconvex, scored on one side, with a uniform smooth surface.
Pharmacotherapeutic group
Tamoxifen is a nonsteroidal antiestrogenic agent that also has weak estrogenic properties. Its action is based on its ability to block estrogen receptors. Tamoxifen, as well as some of its metabolites, compete with estradiol for binding sites with cytoplasmic estrogen receptors in the tissues of the breast, uterus, vagina, anterior pituitary gland and tumors with a high content of estrogen receptors. In contrast to the estrogen receptor complex, the tamoxifen receptor complex does not stimulate DNA synthesis in the nucleus, but inhibits cell division, which leads to regression of tumor cells and their death.
Pharmacokinetics
Action and distribution
After oral administration, tamoxifen is well absorbed. C max ;in serum is achieved within 4 to 7 hours after taking a single dose.
The equilibrium concentration of tamoxifen in the blood serum is usually achieved after 3-4 weeks of administration. Connection with plasma proteins – 99%.
Metabolism and excretion
Metabolized in the liver to form several metabolites.
The elimination of tamoxifen from the body has a biphasic character with an initial T1/2 from 7 to 14 hours and followed by a slow terminal T1/2 for 7 days. It is excreted mainly in the form of conjugates, mainly with feces and only small amounts are excreted in the urine.
Clinical pharmacology
Antiestrogen drug with antitumor effect.
Indications for use
Estrogen-dependent breast cancer in women (especially in menopause) and breast cancer in men.
The drug can be used to treat ovarian cancer, endometrial cancer, kidney cancer, melanoma, soft tissue sarcomas in the presence of estrogen receptors in the tumor, as well as for the treatment of prostate cancer with resistance to other drugs.
Contraindications for use
- Pregnancy;
- lactation period (breastfeeding);
- hypersensitivity to tamoxifen and/or any other ingredient of the drug.
With caution: ;renal failure, diabetes mellitus, eye diseases (including cataracts), deep vein thrombosis and thromboembolic disease (including history), hyperlipidemia, leukopenia, thrombocytoenia, hypercalcemia, concomitant therapy indirect anticoagulants.
