Letrozol Ebrocite (Letrozole)

Letrozole is an aromatase inhibitor used in the management of hormone‑dependent breast cancer.

• Adjuvant treatment of hormone receptor‑positive breast cancer: reduces risk of recurrence in postmenopausal women.
• Metastatic hormone receptor‑positive breast cancer: slows disease progression in postmenopausal women.
• Neoadjuvant therapy for breast cancer: may shrink tumors before surgery in postmenopausal women.

• Letrozole reversibly binds to the aromatase enzyme in peripheral tissues, acting as a non‑competitive inhibitor. This blocks the conversion of androgens to estrogens, leading to markedly lower circulating estrogen levels and consequently diminishing estrogen‑driven proliferation of hormone receptor‑positive breast cancer cells.

Letrozole may cause a range of adverse reactions, which are categorized by frequency.

Common Side Effects

• Hot flashes: sudden feeling of warmth, often with sweating.
• Arthralgia: joint pain or stiffness.
• Fatigue: persistent tiredness not relieved by rest.
• Nausea: mild to moderate upset stomach.
• Headache: intermittent or persistent head pain.
• Dizziness: sensation of light‑headedness.

Serious or Rare Side Effects

• Severe bone loss or osteoporosis: increased fracture risk.
• Venous thromboembolism: deep‑vein thrombosis or pulmonary embolism.
• Elevated liver enzymes: potential hepatic injury.
• Anaphylaxis: rare severe allergic reaction requiring immediate medical attention.

When prescribing Letrozol Ebrocite, clinicians should observe several precautionary measures to ensure patient safety.

• Assess bone health: obtain baseline DEXA scan and consider calcium/vitamin D supplementation.
• Monitor liver function: periodic liver‑function tests are recommended.
• Evaluate cardiovascular risk: avoid in patients with a history of thromboembolic events.
• Contraindicated in pregnancy: do not use in women of childbearing potential without effective contraception.
• Counsel patients on hot flashes and potential bone loss.
• Store at ambient temperature: keep in the original container, protect from moisture and light.

Letrozole can interact with other medicines, affecting its efficacy or safety.

Major Interactions (Avoid)

• Concurrent estrogen replacement therapy: antagonizes letrozole’s effect.
• Strong CYP3A4 inducers (e.g., rifampin, carbamazepine): may markedly reduce plasma concentrations.
• Tamoxifen: opposing mechanisms may diminish therapeutic benefit.

Moderate Interactions (Monitor Closely)

• Warfarin: letrozole may increase INR, requiring closer monitoring.
• CYP2C19 inhibitors (e.g., fluconazole): can raise letrozole levels.
• Statins: monitor for signs of myopathy when combined.