Letrozole Tablets are a non-steroidal aromatase inhibitor used primarily in the treatment of hormone receptor-positive breast cancer in postmenopausal women. It’s also used in infertility treatment to induce ovulation. Letrozole is taken orally and works by lowering estrogen levels, which is critical in treating certain types of breast cancer that are estrogen-dependent.

Mechanism of Action
Inhibits the aromatase enzyme, which converts androgens into estrogens. By reducing estrogen levels, it helps slow the growth of estrogen-dependent cancer cells.

Contraindications & Precautions
Contraindications:
⦁ Hypersensitivity to letrozole or any of its components
⦁ Pre-menopausal women (except in fertility treatment)
Precautions:
⦁ Bone mineral density loss (osteoporosis)
Liver impairment
⦁ Caution in patients with cardiovascular disease or high cholesterol

Interactions
CYP450 inhibitors (e.g., ketoconazole) may increase letrozole levels.
Tamoxifen (used for breast cancer) can reduce its effectiveness.
No significant interactions with other chemotherapy agents.

Adverse Reactions / Side Effects
Hot flashes, fatigue, joint pain, nausea, and headaches.
Serious: Osteoporosis, cardiovascular issues, liver dysfunction, and allergic reactions.

Because it lowers estrogen and can stimulate ovulation, letrozole has been prescribed off-label as a fertility treatment; while the outcomes of pregnancies in one cohort study show comparable rates of ectopic pregnancy and miscarriage in women who used letrozole compared to other medicines for ovarian stimulation; pregnancy should be avoided. Based on postmarketing reports, letrozole can cause fetal injury or death when given during pregnancy even if there are no well-controlled investigations in pregnant women. animal research and how it works. Women who are pregnant or get pregnant while taking letrozole should be informed of the possible risk to the fetus. Use of letrozole during pregnancy produced cases of spontaneous abortions and congenital birth defects in postmarketing studies, yet the data are inadequate to guide a drug-related hazard. Daily treatment of letrozole to rats throughout organogenesis at levels about 0.01 times the highest suggested human dose on a mg/m2 basis produced embryofetal Toxicity including intrauterine death. The same dose level in rabbits led in intrauterine mortality, greater resorption, higher postimplantation loss, and reduced live fetus count. Fetal abnormalities included incomplete ossification of the sternebrae, fore and hind legs, and skull.

Because of the possibility of severe negative effects in nursing newborns from letrozole, counsel women to stop nursing during treatment and for three weeks after the last dose.

Store this medication at 68°F to 77°F (20°C to 25°C) and away from heat, moisture and light. Keep all medicine out of the reach of children. Throw away any unused medicine after the beyond use date. Do not flush unused medications or pour down a sink or drain.

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