Generic Name: Letrozole Brand Name(s): Generics only. No brands available.

Uses

What is Letrozole used for?

This medication is used to treat certain types of breast cancer (such as hormone-receptor-positive breast cancer) in women after menopause. Letrozole is also used to help prevent the cancer from returning. Some breast cancers are made to grow faster by a natural hormone called estrogen. Letrozole decreases the amount of estrogen the body makes and helps to slow or reverse the growth of these breast cancers.

How should I take Letrozole?

Take this medication by mouth, usually once daily with or without food or as directed by your doctor.

Dosage is based on your medical condition and response to treatment.

Use this medication regularly to get the most benefit from it. To help you remember, take it at the same time each day.

Since this drug can be absorbed through the skin and lungs, women who are pregnant should not handle this medication or breathe the dust from the tablets.

Inform your doctor right away if your condition worsens (such as you get new breast lumps).

How do I store Letrozole?

Letrozole is best stored at room temperature away from direct light and moisture. To prevent drug damage, you should not store Letrozole in the bathroom or the freezer. There may be different brands of Letrozole that may have different storage needs. It is important to always check the product package for instructions on storage, or ask your pharmacist. For safety, you should keep all medicines away from children and pets.

You should not flush Letrozole down the toilet or pour them into a drain unless instructed to do so. It is important to properly discard this product when it is expired or no longer needed. Consult your pharmacist for more details about how to safely discard your product.

Precautions & warnings

What should I know before using Letrozole?

Before taking letrozole, tell your doctor or pharmacist if you are allergic to it; or to anastrozole; or if you have any other allergies. This product may contain inactive ingredients, which can cause allergic reactions or other problems. Talk to your pharmacist for more details.

Before using this medication, tell your doctor or pharmacist your medical history, especially of: high blood fats (cholesterol), bone problems (such as osteopenia, osteoporosis), stroke or blood clots, heart disease (such as chest pain, heart attack, heart failure), high blood pressure, kidney problems, liver problems.

This drug may make you dizzy or tired or rarely blur your vision. Alcohol or marijuana can make you more dizzy or tired. Do not drive, use machinery, or do anything that needs alertness or clear vision until you can do it safely. Limit alcoholic beverages. Talk to your doctor if you are using marijuana.

Before having surgery, tell your doctor or dentist about all the products you use (including prescription drugs, nonprescription drugs, and herbal products).

This medication must not be used during pregnancy. It may harm an unborn baby. Letrozole is used mainly in women after menopause. If you have recently gone through menopause, discuss the need for use of reliable forms of birth control while taking this medication and for 3 weeks after stopping treatment with your doctor. Do not use birth control products containing estrogen. Consult your doctor for more details. If you become pregnant or think you may be pregnant, tell your doctor right away.

It is unknown if this drug passes into breast milk. Because of the possible risk to the infant, breast-feeding while using this drug and for at least 3 weeks after stopping treatment is not recommended. Consult your doctor before breast-feeding.

Is it safe during pregnancy or breast-feeding?

There are no adequate studies in women for determining risk when using this Letrozole during pregnancy or while breastfeeding. Please always consult with your doctor to weigh the potential benefits and risks before taking Letrozole. Letrozole is pregnancy risk category X according to the US Food and Drug Administration (FDA).

FDA pregnancy risk category reference below:

  • A=No risk,
  • B=No risk in some studies,
  • C=There may be some risk,
  • D=Positive evidence of risk,
  • X=Contraindicated,
  • N=Unknown

Side effects

What side effects can occur from Letrozole?

Hot flashes, hair loss, joint/bone/muscle pain, tiredness, unusual sweating, nausea, diarrhea, dizziness, and trouble sleeping may occur. If any of these effects persist or worsen, notify your doctor or pharmacist promptly.

Remember that your doctor has prescribed this medication because he or she has judged that the benefit to you is greater than the risk of side effects. Many people using this medication do not have serious side effects.

Tell your doctor right away if you have any serious side effects, including: bone fractures, mental/mood changes (such as depression, anxiety), swelling of arms/legs, blurred vision, persistent nausea/vomiting, unusual tiredness, dark urine, yellowing eyes/skin..

This medication (and cancer) may rarely cause serious problems from blood clots (such as heart attack or stroke). Get medical help right away if you experience: sudden shortness of breath, chest/jaw/left arm pain, confusion, coughing up blood, sudden dizziness/fainting, pain/swelling/warmth in the groin/calf, tingling/weakness/numbness in the arms/legs, slurred speech, weakness on one side of the body, vision changes, sudden/severe headache.

A very serious allergic reaction to this drug is rare. However, get medical help right away if you notice any symptoms of a serious allergic reaction, including: rash, itching/swelling (especially of the face/tongue/throat/neck), severe dizziness, trouble breathing.

Not everyone experiences these side effects. There may be some side effects not listed above. If you have any concerns about a side-effect, please consult your doctor or pharmacist.

Interactions

What drugs may interact with Letrozole?

Some products that may interact with this drug include: estrogens (such as ethinyl estradiol, conjugated estrogens), estrogen blockers (such as anastrozole, tamoxifen).

Letrozole may interact with other drugs that you are currently taking, which can change how your drug works or increase your risk for serious side effects. To avoid any potential drug interactions, you should keep a list of all the drugs you are using (including prescription drugs, nonprescription drugs and herbal products) and share it with your doctor and pharmacist. For your safety, do not start, stop, or change the dosage of any drugs without your doctor’s approval.

Does food or alcohol interact with Letrozole?

Letrozole may interact with food or alcohol by altering the way the drug works or increase the risk for serious side effects. Please discuss with your doctor or pharmacist any potential food or alcohol interactions before using this drug.

What health conditions may interact with Letrozole?

Letrozole may interact with your health condition. This interaction may worsen your health condition or alter the way the drug works. It is important to always let your doctor and pharmacist know all the health conditions you currently have.

Dosage

The information provided is not a substitute for any medical advice. You should ALWAYS consult with your doctor or pharmacist before using this Letrozole.

What is the dose of Letrozole for an adult?

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 treatment 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 treatment 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.

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.

What is the dose of Letrozole for a child?

The dosage has not been established in pediatric patients. It may be unsafe for your child. It is always important to fully understand the safety of the drug before using. Please consult with your doctor or pharmacist for more information.

How is Letrozole available?

Letrozole is available in the following dosage forms and strengths:

  • Oral Tablet

What should I do in case of an emergency or overdose?

In case of an emergency or an overdose, call your local emergency services or go to your nearest emergency room.

What should I do if I miss a dose?

If you miss a dose of Letrozole, take it as soon as possible. However, if it is almost time for your next dose, skip the missed dose and take your regular dose as scheduled. Do not take a double dose.

 

Hello Health Group does not provide medical advice, diagnosis or treatment.

Sources

Review Date: March 14, 2018 | Last Modified: March 14, 2018

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