About letrozol
Aromatase inhibitor; anticancer medicine
Used for
- Treats hormone receptor-positive breast cancer in postmenopausal adults
- May reduce breast cancer recurrence after surgery
- May treat advanced breast cancer
Usual adult dose
2.5 mg by mouth once daily; treatment duration depends on the cancer and treatment plan.
Common side effects
- Hot flushes and sweating
- Joint or bone pain
- Fatigue
- Increased cholesterol
Important warnings
- Can cause bone loss and fractures; bone health may need monitoring.
- May cause dizziness or fatigue; use caution with activities requiring alertness.
- Can harm a fetus; pregnancy must be avoided during treatment.
- Not intended for premenopausal patients unless ovarian function is medically suppressed.
Pregnancy
Can cause fetal harm and is contraindicated during pregnancy. Effective contraception is needed during treatment and for at least three weeks after the last dose.
Breastfeeding
Do not breastfeed during treatment and for at least three weeks after the last dose.
Interactions
- Tamoxifen and estrogen-containing medicines can reduce letrozole levels or effect.
- Rifampin may reduce letrozole levels.
- Certain seizure medicines, such as phenytoin, may reduce letrozole levels.
AI-generated from general medical knowledge, not from this product's official leaflet. It may be incomplete or out of date. Not medical advice — ask a pharmacist or doctor before making any decision.