Femara (Generic: Letrozole) belongs to a group of drugs known as an aromatase inhibitor. It is used in the treatment of specific types of breast cancer in postmenopausal women.
Although it is approved by the FDA for breast cancer, it may also be used to stimulate ovulation in women with polycystic ovary syndrome (PCOS) and unexplained infertility.
Many fertility specialists recommend Femara over Clomiphene citrate because it has fewer side effects than Clomid, and there is a lower chance of multiple pregnancies. The second reason is, it is used in people with Clomid resistance.
Originally manufactured by Novartis, Femara was approved in 1997 by the Food and Drug Administration (FDA).
- Letrozole has been used in Estrogen receptor-positive early breast cancer in postmenopausal women.
- It is also used in early invasive breast cancer in postmenopausal ladies when five years of tamoxifen therapy have failed to work.
- It is used in advanced breast cancer in postmenopausal women.
- It is additionally employed in pre-operative treatment in postmenopausal women with localized hormone receptor-positive breast cancer.
- Femara is most commonly used in unexplained infertility. (off-label use)
- It is used to stimulate ovulation in women with polycystic ovary syndrome (PCOS).
Note: Your doctor may have suggested this medication for conditions other than those listed in this medication guide.
It is contraindicated by the following conditions:
- Premenopausal women
- Liver disease (especially cirrhosis)
- It is contraindicated in people allergic to the active ingredient present or any of the excipients.
- Osteopenia (low bone mineral density),
- High cholesterol; or
- If you also take tamoxifen.
- The use of Femara might cause decreases in the density of your bones and increase bone fractures and osteoporosis.
- Avoid if you are under 18 years of age.
Before taking this drug,
- Tell your doctor or pharmacist if you are allergic to Femara or any other ingredients in this medication.
- Tell your GP if you have high cholesterol, liver disease, and osteoporosis.
- Tell your doctor about your current as well as past medical history. Tell him your other prescriptions, and non-prescription drugs, nutritional supplements you are taking.
- Tell Your Doctor if you are pregnant or planning to become pregnant before starting Femara.
- Don’t take Femara if you still have periods. This drug is only used in women who are no longer having periods.
- Always check the expiry date and Don’t take it after the Expiry date printed on the packing.
Mechanism Of Action
Letrozole is a selective nonsteroidal inhibitor of the aromatase enzyme system; it inhibits the conversion of androgens to estrogens.
In adult nontumor- and tumor-bearing females, Letrozole is as effective as ovariectomy in reducing uterine weight. It also causes elevating blood serum luteinizing hormone and inflicts the regression of estrogen-dependent tumors. In distinction to ovariectomy, treatment with Letrozole doesn’t cause a rise in serum follicle-stimulating hormone.
Letrozole selectively inhibits gonadal steroidogenesis but has no important effect on adrenal mineralocorticoid or glucocorticoid synthesis.
Letrozole inhibits the aromatase enzyme by competitively binding to the heme of the cytochrome P450 subunit of the enzyme. This inhibition leads to a reduction of estrogen synthesis in all tissues.
Treatment of women with Letrozole significantly lowers blood serum estrone, estradiol, and estrone sulfate. However, it has not been shown to affect adrenal corticosteroid synthesis, aldosterone synthesis, or the synthesis of thyroid hormones.
Letrozole (Femara Tablet) is quickly absorbed with 100% bioavailability. However, it has a slow metabolism, a large volume of Distribution, and a Time half (t½) of approximately 40 hours.
If you take other medicines or over-the-counter medicines simultaneously, the effects of Femara Tablet may change. This may increase the risk of side effects or make your medications not work correctly. Tell your doctor about all the medicines, supplements, herbal remedies, and vitamins you use. Femara can interact with the following medications:
- Don’t Take Letrozole if you are already taking tamoxifen.
- While interaction with warfarin showed no clinical effect of Letrozole on warfarin pharmacokinetics.
- Cimetidine showed no clinically significant effect on letrozole pharmacokinetics.
- Femara may also interact with Estrogens (Conjugated estrogens and Ethinyl estradiol).
- Avoid eating grapefruit and drinking grapefruit juice while taking Letrozole because it slows down the breakdown of Letrozole. This could cause letrozole levels in the blood to rise dangerously high.
- Alcohol or marijuana can make you dizzier. Limit alcohol while taking Femara.
- It may also interact with Citalopram, Thalidomide, and Clopidogrel.
- It may also interact with Birth Control pills.
- According to a study published in the Journal, of Cell Chemical Biology suggests that exposure to the Estrogen mimicking compound could significantly reduce the effectiveness of anti-estrogen therapies like the Letrozole and palbociclib combination.
Femara Side Effects
It is beneficial for treating and improving the conditions mentioned above, but Femara has specific side effects. Like any other medicine, Femara can cause some side effects along with its beneficial effects. Therefore, it is essential to know the side effects before taking it.
Most people do not feel all the side effects of Femara. Side effects are often predictable in terms of appearance and duration. In addition, the side effects of Femara are almost always reversible and disappear once treatment is complete. The following is a list of possible side effects that may occur from using this medicine;
Most common Femara Side effects
The most common side effects from this medication include:
- Hot flushes,
- Raised sweating,
- Increased craving,
- Peripheral edema,
- Skin rashes,
- Bone fracture,
- Osteoporosis etc.
Less Common Side Effects
Less common side effects from Femara Tablet include
- High blood pressure,
- Memory impairment,
- Taste disturbance,
- Dry skin,
- Urinary frequency,
- Abdominal pain,
- Urinary tract infection,
- Viginal discharge,
- Vigina bleeding,
- Breast pain,
- Blurred vision,
- Eye irritation,
- Carpal tunnel syndrome,
- Tumor pain, and
- General edema.
Rare Femara side effects
Infrequent side effect from Femara Tablet includes:
- Arterial thrombosis,
- Cerebrovascular infarction, and
Note: This is not a complete list of Femara side effects. Stop using This drug and Consult your doctors if You experience the above products or other serious side effects from Femara Tablet.
Femara In Pregnancy & Breast Feeding
- Letrozole should be avoided in pregnant women because it causes congenital disabilities in a child. Manufacturer recommendation the use of contraceptives until postmenopausal status is established.
- While just in the case of lactating women, it’s unknown if Letrozole is present in human milk. There isn’t any information on the effects of Letrozole on breastfed infants or milk production.
- The standard recommended dose of Letrozole for all types of breast cancer treatment is 2.5 mg per day.
- The duration of therapy is usually 5 years, but some doctors may recommend it for a more extended period.
- You can take without regard to meals.
- If you believe that you have taken an overdose, contact an emergency room or poison center.
- If you miss a dose of Letrozole, try to take it as soon as you remember.
- However, if it is almost time for your next dose, skip the missed dose and continue with your regular dosing schedule.
- Do not take extra doses to make up for lost ones.
Frequently Asked Questions
Q. 1 What is Femara?
It is a selective nonsteroidal inhibitor of the aromatase enzyme system; it inhibits the conversion of androgens to Estrogen. It is used in breast cancer and infertility.
Q.2 Is it safe to use Femara Tablet during pregnancy & Breastfeeding?
No, the use of this drug is not recommended in pregnant and breastfeeding women.
Q.3 Is Femara a Chemotherapy?
No, Femara belongs to hormonal therapy drugs. Hormonal therapies require the presence of specific receptors (binding sites) in the cancer cell for Estrogen and progesterone. Most hormonal therapies are medications taken daily in the form of tablets. Breast cancer that has neither Estrogen nor progesterone receptors does not respond to hormone therapy.
Q.4 Can I stop immediately, or can I slow down my consumption?
Some medications should be immediately reduced or stopped due to rebound effects. Consult your doctor for specific recommendations for your body, health, and other medicines that you may use.
Q.5 Is it safe to drive or use heavy machinery when used?
You should not drive if you feel tired, dizzy, or have low blood pressure by taking the Femara Tablets. Pharmacists also recommend that patients do not drink alcohol with medication as alcohol increases the side effects of drowsiness. Please check these effects on your body when using Femara Tablet. Always consult your doctor for particular recommendations on your body and health.
Q.6 Is Femara cause addiction or adaptation?
Most medicines have no abuse. Do not medicate yourself and increase the body’s dependence on medication without the advice of a doctor.
Q.7 Can you drink while on Letrozole (Femara)?
Letrozole and alcohol can both cause headaches and nausea. These side effects may worsen if you take both drugs at the same time. If possible, try to avoid or restrict alcohol consumption while taking Letrozole. Always consult your doctor before using this drug with Others.
Q.8 Does Femara increase the chances of getting pregnant?
With this drug, a woman’s pregnancy chances increase by about 15% per month. Ovulation was successful in women who did not ovulate naturally. The combined use of Femara with other drugs significantly increases a woman’s chance of pregnancy.
Q.9 Does it cause hair loss?
Some women who take Letrozole and other such drugs can experience hair loss due to the estrogenic effects of these treatments. However, these treatments are unlikely to result in complete hair loss.
Q.10 Can Femara cause multiple births?
According to the Centers for disease control & Prevention, Fertility treatments of all types can increase the chances of multiple births.
Another study published in the New England Journal Of Medicine, The percentage of multiple pregnancies is more in the case of Letrozole as compared to clomiphene.
Q.11 Can Femara cause congenital disabilities?
If taken during pregnancy, Femara can cause congenital disabilities. However, when taken to induce ovulation, Femara appears to be safe.
Q. 12 How much does Femara cost?
The price of a 2.5 mg Femara tablet is approximately $ 750 for a 30 tablets strip. This Femara cost is for cash-paying customers only and is not valid with insurance plans. The latest version of this brand is covered by 73% of the insurance plans with a share of 60 to 80$. However, some pharmacy vouchers or cash prizes may be lower.
Q. 13 Do Femara’s side effects go away?
Side effects from using this drug are 1% in the majority of the patients, and These side effects are reversible. Some side effects may go away on their own over time. Contact your physician.
Q. 14 How long should I stay on Letrozole?
Suggested hormonal therapy is ten years: First 5 years of tamoxifen and then the next 5 years of Femara. But you should consult your healthcare provider about how long you can expect to take it.
Q. 15 When should I take Femara?
The usual recommended dose for fertility purposes is 2.5 mg every day for 5-7 days. The ideal time to begin is on the third or fourth day of the cycle.
The usual recommended dose of Letrozole for all types of breast cancer treatment is 2.5 mg per day. You can take it without regard to meals. The duration of therapy is usually 5 years, but some doctors may recommend it for a more extended period.
Q. 16 What are the benefits of taking Letrozole?
It inhibits the conversion of androgens to Estrogen. That’s why Femara has been used in Estrogen receptor-positive early breast cancer in postmenopausal women and other types of breast cancer. It improves the chance of survival as it helps to lower your risk of breast cancer recurrence.
It is also used in the treatment of infertility.
Q. 17 Does Letrozole cause bone pain?
Femara can drop your estrogen levels which ultimately can cause pain in the joint and muscles.
Q. 18 How does Femara work?
Femara inhibits the aromatase enzyme by competitively binding to the heme of the cytochrome P450 subunit of the enzyme. This inhibition leads to a reduction of estrogen synthesis in all tissues.
When taking medicine, prevents the androgens in your body from converting into Estrogen. When Estrogen is blocked, the pituitary gland receives the required message for the production of follicle-stimulating hormone (FSH), which stimulates the production of an ovary egg.
Treatment of women with this medicine significantly lowers blood serum estrone, estradiol, and estrone sulfate. However, it has not been shown to dramatically affect adrenal corticosteroid synthesis, aldosterone synthesis, or synthesis of thyroid hormones.
Q. 19 How to take Femara to get pregnant?
Letrozole is usually taken once daily for five days. If you started treatment on day 3, you probably ovulated once between day 14 and day 17 of your cycle. To think, you will start having sex before ovulating. You would probably ovulate between the 16th and 19th days if you started the treatment on the fifth day.
Q. 20 How do you take Femara for infertility?
Take two pills daily, starting on Cycle Day 3 and ending on Cycle Day 7.
You can take the two tablets together, but you have to take them for five consistent days. After that, you can take it any time of day.
Note: The first day of menses is Cycle Day 1.
Q.21 Are Femara and letrozole the same?
It is the brand name of Letrozole manufactured by Novartis Pharmaceutical company. They both are the same thing, but Femara is a brand, and Letrozole is Generic.
Q. 22 What is the generic for Femara?
The generic of Femara is Letrozole, which is a nonsteroidal aromatase inhibitor. It is used to treat breast cancer in postmenopausal women.
Please Feel free to ask any questions related to this topic in the comments section.
- Letrozole: a review of its use in postmenopausal women with breast cancer. [Internet]. [Cited December 2018]. Available from: https://www.ncbi.nlm.nih.gov/m/pubmed/15161328/
- Long-term efficacy and safety of Letrozole for the adjuvant treatment of early breast cancer in postmenopausal women: a review. [Internet]. [Cited December 2018]. Available from: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2747391/
- Femara Full Prescribing Information. [Internet]. [Cited December 2018]. Available From: https://www.pharma.us.novartis.com/sites/www.pharma.us.novartis.com/files/Femara.pdf
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6 thoughts on “Femara (Letrozole): Uses, Side Effects, Dosage & FAQs”
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