Tamoxifen improves fertility in males with infertility by disinhibiting the hypothalamic–pituitary–gonadal axis (HPG axis) via ER antagonism and thereby increasing the secretion of luteinizing hormone (LH) and follicle-stimulating hormone (FSH) and increasing testicular testosterone production.
Tamoxifen is used to prevent and treat gynecomastia. It is taken as a preventative measure in small doses, or used at the onset of any symptoms such as nipple soreness or sensitivity. Other medications are taken for similar purposes such as clomifene and the anti-aromatase drugs which are used in order to try to avoid the hormone-related adverse effects.
Tamoxifen is useful in the treatment of peripheral precocious puberty, for instance due to McCune–Albright syndrome, in both girls and boys. It has been found to decrease growth velocity and the rate of bone maturation in girls with precocious puberty, and hence to improve final height in these individuals.
Tamoxifen has a number of contraindications, including known hypersensitivity to tamoxifen or other ingredients, individuals taking concomitant coumarin-type anticoagulant therapy, and women with a history of venous thromboembolism (deep vein thrombosis or pulmonary embolism).