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How do you take Femara? What days do you take it?

Medically reviewed by Carmen Pope, BPharm. Last updated on July 1, 2024.

Official answer

by Drugs.com
  • For fertility issues and PCOS, Femara is typically taken once a day for five days.
  • Femara is usually started on day three or four of your monthly cycle (the first day of your monthly cycle is the first day of your period) and then taken for five days.
  • If you are taking Femara for breast cancer, it is usually taken once a day or once every other day.

Femara (letrozole) is a prescription medication used for the treatment of breast cancer and it is also commonly used off-label to treat ovulation problems including polycystic ovary syndrome (PCOS) and unexplained infertility.

For fertility issues and PCOS, Femara is typically taken once a day for five days. It is usually started on day three or four of your monthly cycle (the first day of your monthly cycle is the first day of your period) and then you ovulate about four to seven days after taking the last of the five pills. This means that if you started the pills on day one of your period then you should ovulate between days nine to twelve. Intercourse or intrauterine insemination (the artificial insertion of sperm) is timed to coincide with ovulation.

For breast cancer, Femara is usually taken once a day or once every other day.

References
  • Femara (letrozole) Novartis Pharmaceuticals Corporation https://www.drugs.com/pro/femara.html
  • Legro R, Brzyski R, Diamond M, et al. Letrozole versus Clomiphene for Infertility in the Polycystic Ovary Syndrome. N Engl J Med 2014; 371:119-129 DOI: 10.1056/NEJMoa1313517 Franik S,
  • Eltrop SM, Kremer JA, Kiesel L, Farquhar C. Aromatase inhibitors (letrozole) for subfertile women with polycystic ovary syndrome. Cochrane Database Syst Rev. 2018;5(5): CD010287. Published 2018 May 24. DOI:10.1002/14651858.CD010287.pub3

Read next

What are the benefits of taking Kisqali and Femara together?

Taking Kisqali and Femara together can benefit patients with specific types of breast cancer because the medications work in different ways. Kisqali blocks the growth of cancer cells, while Femara reduces the amount of estrogen in the body that can fuel cancer growth. Studies have shown that taking the two together can be more effective compared to taking Femara alone. Continue reading

How long do letrozole side effects last?

Most side effects of letrozole are mild and temporary, lasting only a few days or weeks until your body gets used to taking the medication. Some other side effects of letrozole take a few months to develop and tend to persist long term until you stop taking letrozole. The half-life of letrozole is 2 days, so once you stop taking letrozole, you might continue to experience side effects for about a week to 10 days after your last dose. Continue reading

What happens when you stop taking letrozole?

When you stop taking letrozole, side effects such as swelling, cough, hot flashes, and nausea, should improve within a week or 10 days. Some, such as high cholesterol, bone loss, and hair thinning may take many months to resolve. As long as you have taken it for at least 5 years, then letrozole should continue to reduce the risk of breast cancer coming back for many years after you stop taking it. Letrozole is usually taken for 5 years, but may be recommended for up to 10 years depending on individual circumstances. Continue reading

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