Track letrozole in Peptimes™
Letrozole is a nonsteroidal aromatase inhibitor (an inhibitor of estrogen synthesis). It is the active ingredient in Femara and generic letrozole tablets, FDA-approved prescription medicines taken by mouth. (Source: DailyMed label.)
Is letrozole FDA-approved?
Yes, as specific products: Femara tablets and generic letrozole tablets are FDA-approved for the uses in their labels, and they're prescription only.
Letrozole
Also: Femara, CGS-20267
- Status label in the Peptimes Library
- FDA Approved
- Routes in Peptimes
- Oral
- Updated
- 1 Nov 2026
US regulatory status
FDA approval belongs to each product below, for its route and the uses in its label. Label uses are shortened unless quoted.
Femara (letrozole) tablets
Oral
The uses in its label.
Source: DailyMed label, checked 1 Nov 2026
Generic letrozole tablets, from several manufacturers
Oral
As stated on each product's label (approved through abbreviated new drug applications, ANDAs).
Source: Drugs@FDA, checked 1 Nov 2026
Investigational
No, for the products and uses above.
Source: Drugs@FDA, checked 1 Nov 2026
What studies have looked at
Each point says who or what was studied and what the study reported, with its source and the date we checked it. These are findings from the sources cited, not advice or a promise of any result.
- In humans
A placebo-controlled trial in 5,187 postmenopausal women who had completed earlier tamoxifen treatment for early breast cancer: at a median 2.4 years, there were fewer recurrences or new cancers in the other breast with letrozole (75) than with placebo (132). Deaths didn't differ significantly.
Source: PMID 14551341, checked 1 Nov 2026
How to track it in Peptimes
Add letrozole in My Protocols and set the schedule you already follow: days of the week, times of day and a start date. Peptimes never suggests an amount when you log or schedule a dose. Its Library entry shows the status label “FDA Approved”; the list above gives the detail by product.
- Logging: the amount you took and how you feel. It’s logged as oral, so there’s no injection site to record.
- Reminders and history: reminders at your times, Dose History, the Calendar and CSV or JSON export work as described on the peptide tracker app page.
Peptimes is a tracking app, not medical advice. Talk to a licensed clinician about your treatment. Peptimes doesn’t sell letrozole or any other compound.
More sources
- FDA, Drugs@FDA, NDA 020726 (Femara), checked 1 Nov 2026: product, route and marketing status.
- FDA, Global Substance Registration System, Letrozole, checked 1 Nov 2026: the code name CGS-20267.
Related pages
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