Femara (letrozole) is a nonsteroidal aromatase inhibitor indicated for the adjuvant treatment of postmenopausal women with hormone receptor-positive early breast cancer. It is also approved for the extended adjuvant treatment of early breast cancer in postmenopausal women who have received standard tamoxifen therapy, and for the first-line treatment of postmenopausal women with hormone receptor-positive or unknown locally advanced or metastatic breast cancer. By significantly reducing estrogen production, Femara targets the hormonal drivers of certain breast cancers, offering a targeted mechanism of action that has demonstrated efficacy in large-scale clinical trials. Its use represents a cornerstone in the endocrine management of hormone-sensitive malignancies.

Features

• Contains letrozole 2.5 mg as the active pharmaceutical ingredient
• Nonsteroidal aromatase inhibitor class medication
• Available in film-coated, biconvex tablets
• Administered orally once daily, with or without food
• Manufactured under strict pharmaceutical quality control standards
• Typically supplied in bottles of 30 tablets

Benefits

• Demonstrated improvement in disease-free survival in adjuvant breast cancer treatment
• Significant reduction in contralateral breast cancer incidence
• Effective estrogen suppression through aromatase enzyme inhibition
• Generally well-tolerated profile compared to some chemotherapeutic agents
• Oral administration convenience supporting treatment adherence
• Established efficacy in both early and advanced breast cancer settings

Common use

Femara is primarily prescribed for the treatment of hormone receptor-positive breast cancer in postmenopausal women. In the adjuvant setting, it is used following primary treatment (surgery, radiation, or chemotherapy) to reduce the risk of cancer recurrence. For metastatic disease, it serves as first-line endocrine therapy. Additionally, it may be used in ovulation induction protocols under specialist supervision, though this represents an off-label application. The medication is typically prescribed as part of a comprehensive oncology treatment plan developed by a multidisciplinary team.

Dosage and direction

The recommended dose of Femara is 2.5 mg administered orally once daily, with or without food. For adjuvant treatment of early breast cancer, treatment should continue for 5 years unless disease recurrence or unacceptable toxicity occurs. For extended adjuvant treatment, therapy begins after completing 5 years of tamoxifen treatment. In metastatic settings, treatment continues until tumor progression is documented. Tablets should be swallowed whole with water and not crushed or chewed. Dosing adjustments are generally not required for elderly patients but may be necessary in those with severe hepatic impairment.

Precautions

Patients should undergo comprehensive assessment of menopausal status before initiation, as Femara is not indicated for premenopausal women. Regular monitoring of bone mineral density is recommended due to the potential for accelerated bone loss. Hepatic function should be assessed periodically, particularly in patients with pre-existing liver conditions. Patients with a history of osteoporosis or at high risk for fractures may require additional bone-protective therapy. Caution is advised in patients with severe renal impairment (CrCl <30 mL/min). Regular follow-up including assessment of lipid profiles may be warranted in some patients.

Contraindications

Femara is contraindicated in women who are pregnant or may become pregnant, as it may cause fetal harm. It is also contraindicated in premenopausal women without concomitant luteinizing hormone-releasing hormone (LHRH) agonist therapy. Patients with known hypersensitivity to letrozole or any components of the formulation should not receive this medication. The drug is not indicated for use in pediatric populations. Concomitant therapy with estrogen-containing medications is contraindicated as it may interfere with Femara’s pharmacological activity.

Possible side effects

Common adverse reactions (≥10%) include hot flashes, arthralgia, fatigue, increased sweating, and hypercholesterolemia. Other frequently reported effects include nausea, headache, back pain, and dizziness. Serious but less common side effects may include osteoporosis and fractures, cardiovascular events, and elevated transaminases. Approximately 3% of patients discontinue treatment due to adverse events, most commonly musculoskeletal disorders. Patients should report any persistent or severe symptoms to their healthcare provider promptly.

Drug interaction

Femara is primarily metabolized by CYP3A4 and CYP2A6 enzymes. Concomitant use with strong CYP3A4 inhibitors (e.g., ketoconazole, ritonavir) may increase letrozole concentrations, though dose adjustment is generally not recommended. CYP3A4 inducers (e.g., rifampicin, phenytoin) may decrease letrozole exposure. Tamoxifen may reduce letrozole plasma concentrations by approximately 38% and concurrent use is not recommended. No clinically significant interactions have been observed with warfarin, cimetidine, or other commonly co-administered medications.

Missed dose

If a dose is missed, it should be taken as soon as remembered unless it is nearly time for the next scheduled dose. In that case, the missed dose should be skipped and the regular dosing schedule resumed. Patients should not take a double dose to make up for a missed dose. Maintaining consistent dosing is important for optimal therapeutic effect, and patients should discuss any pattern of missed doses with their healthcare provider to address adherence issues.

Overdose

Limited information is available regarding Femara overdose. Single doses up to 62.5 mg have been administered without serious adverse effects. In case of suspected overdose, symptomatic and supportive care is recommended. Dialysis is unlikely to be beneficial due to Femara’s high protein binding. Medical attention should be sought immediately if overdose is suspected. Healthcare providers should contact a poison control center for current management recommendations.

Storage

Store Femara tablets at room temperature (20-25°C or 68-77°F), with excursions permitted between 15-30°C (59-86°F). Keep the container tightly closed and protect from moisture and light. Keep out of reach of children and pets. Do not use beyond the expiration date printed on the packaging. Proper disposal of unused medication should follow local regulations, typically through medication take-back programs.

Disclaimer

This information is provided for educational purposes only and does not constitute medical advice. Treatment decisions should be made in consultation with a qualified healthcare professional familiar with the patient’s individual medical history and current condition. The prescribing physician should be consulted regarding specific indications, contraindications, warnings, and precautions associated with Femara therapy.

Reviews

Clinical trials have demonstrated Femara’s efficacy in breast cancer treatment. The BIG 1-98 trial showed significant improvement in disease-free survival compared to tamoxifen in postmenopausal women with hormone receptor-positive early breast cancer. The MA-17 trial established the benefit of extended adjuvant therapy with letrozole after tamoxifen completion. Many oncologists report favorable experiences with Femara in clinical practice, noting its generally manageable side effect profile and established efficacy data. Patient experiences vary, with many appreciating the oral administration format while some report challenges with musculoskeletal side effects.