Letrozole Dosage
Medically reviewed by Drugs.com. Last updated on May 6, 2024.
Applies to the following strengths: 2.5 mg
Usual Adult Dose for:
Additional dosage information:
Usual Adult Dose for Breast Cancer
2.5 mg orally once a day
Duration of therapy:
- Adjuvant and extended adjuvant settings: Optimal duration is unknown; discontinue therapy at relapse.
- Advanced disease: Until tumor progression is evident.
Uses:
- Adjuvant treatment of postmenopausal women with hormone receptor positive early breast cancer
- Extended adjuvant treatment of early breast cancer in postmenopausal women who have received 5 years of adjuvant tamoxifen therapy
- First-line treatment of advanced breast cancer in postmenopausal women with hormone receptor positive or unknown locally advanced or metastatic breast cancer; second-line treatment of advanced breast cancer in postmenopausal women with disease progression following antiestrogen therapy
Usual Adult Dose for Breast Cancer - Adjuvant
2.5 mg orally once a day
Duration of therapy:
- Adjuvant and extended adjuvant settings: Optimal duration is unknown; discontinue therapy at relapse.
- Advanced disease: Until tumor progression is evident.
Uses:
- Adjuvant treatment of postmenopausal women with hormone receptor positive early breast cancer
- Extended adjuvant treatment of early breast cancer in postmenopausal women who have received 5 years of adjuvant tamoxifen therapy
- First-line treatment of advanced breast cancer in postmenopausal women with hormone receptor positive or unknown locally advanced or metastatic breast cancer; second-line treatment of advanced breast cancer in postmenopausal women with disease progression following antiestrogen therapy
Renal Dose Adjustments
CrCl 10 mL/min or greater: No adjustment recommended.
CrCl less than 10 mL/min: Data not available
Liver Dose Adjustments
Mild to moderate hepatic impairment: No adjustment recommended.
Severe hepatic impairment with cirrhosis: 2.5 mg orally every other day
Noncirrhotic with elevated bilirubin: Data not available
Precautions
CONTRAINDICATIONS:
- Hypersensitivity to the active component or any of the ingredients
- Pregnancy
Safety and efficacy have not been established in patients younger than 18 years.
Consult WARNINGS section for additional precautions.
Dialysis
This drug is anticipated to be dialyzable; however, no dose adjustment guidelines have been reported.
Other Comments
Administration Advice:
- Take this drug without regard to meals.
- Use this drug only in women with clearly established postmenopausal status. In patients whose menopausal status is unclear, measure luteinizing hormone (LH), follicle-stimulating hormone (FSH) and/or estradiol levels before initiating treatment.
- Skip a missed dose if it is within 2 or 3 hours of the next dose; otherwise, take the missed dose as soon as possible and then return to the regular dosing schedule.
Storage Requirements:
Store this drug at room temperature (20 to 25 Celsius) and protect from light.
General:
- The clinical benefit of this drug in premenopausal women with breast cancer has not been determined.
- Efficacy of this drug has not been demonstrated in patients with hormone receptor negative breast cancer.
- Use of this drug in men with breast cancer has not been studied.
- Specific treatment for overdosage is not known.
Monitoring:
- Bone mineral density
- Serum cholesterol
Patient Advice:
This drug may cause fatigue, dizziness, and drowsiness; avoid driving or any other potentially dangerous activity until you know how this drug affects you.
Frequently asked questions
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