Anastrozole : Uses, Side Effects, Interactions & More
Why is this medication prescribed?
Anastrozole is used with other treatments, such as surgery or radiation, to treat early breast cancer in women who have experienced menopause (change of life; end of monthly menstrual periods). This drug is also used in women who have experienced menopause, as the first treatment for breast cancer that has spread within the breast or other areas of the body. This drug is also used to treat breast cancer in women whose breast cancer has worsened after taking tamoxifen (Nolvadex). Anastrozole is in a class of medications called non-steroidal aromatase inhibitors. It works by decreasing the amount of estrogen the body makes. This can slow or stop the growth of many types of breast cancer cells that need estrogen to grow.
How should this medicine be used?
Anastrozole comes as a tablet to take by mouth. It is usually taken once a day with or without food. Take anastrozole at around the same times every day. Follow the directions on your prescription label carefully, and ask your doctor or pharmacist to explain any parts you don’t understand. Take anastrozole exactly as directed. Do not take more or less, or take it more often than prescribed by your doctor.
You may need to take anastrozole for several years or more. Keep taking anastrozole even if you feel fine. Do not stop taking anastrozole without consulting your doctor.
Ask your pharmacist or doctor for a copy of the manufacturer’s information for the patient.
Other uses for this medicine
Anastrozole is also sometimes used to prevent breast cancer in women who are at high risk of developing the disease. Talk to your doctor about the risks of using this drug for your condition.
This medicine may be prescribed for other uses; ask your doctor or pharmacist for more information.
What special precautions should I follow?
Before taking anastrozole,
- Tell your doctor and pharmacist if you are allergic to anastrozole, any other medications, or any of the ingredients in anastrozole. Ask your pharmacist for a list of the ingredients.
- Tell your doctor and pharmacist what other prescription and nonprescription medications, vitamins, nutritional supplements, and herbal products you are taking or plan to take. Be sure to mention any of the following: estrogen-containing medications, such as hormone replacement therapy (HRT) and hormonal contraceptives (birth control pills, patches, rings, and injections); raloxifene (Evista); and tamoxifen (Nolvadex). Your doctor may need to change the doses of your medications or monitor you closely for side effects.
- Tell your doctor if you have or have ever had high cholesterol, osteoporosis (a condition in which the bones are brittle and break easily), liver or heart disease.
- You should know that only women who have gone through menopause and cannot get pregnant should take anastrozole. However, if you are pregnant or breastfeeding, you should inform your doctor before you start taking this medicine. Anastrozole can harm the fetus.
What special dietary instructions should I follow?
Unless your doctor tells you otherwise, continue your normal diet.
What should I do if I forget a dose?
Take the missed dose as soon as you remember. However, if it is almost time for the next dose, skip the missed dose and continue your regular dosing schedule. Do not take a double dose to make up for the one you forgot.
What side effects can this medication cause?
Anastrozole may cause side effects. Tell your doctor if any of these symptoms are severe or do not go away:
- hot flashes
- stomach pain
- loss of appetite
- weight gain
- joint, bone, or muscle pain
- breast pain
- mood changes
- difficulty falling asleep or staying asleep
- vaginal bleeding
- vaginal dryness or irritation
- pain, burning, or tingling in the hands or feet
- dry mouth
- hair thinning
Some side effects can be serious. If you experience any of these symptoms, call your doctor immediately:
- chest pain
- sore throat, cough, fever, chills, swollen glands, or other signs of infection
- swelling, redness, or warmth in hand or arm
- difficult, painful, or urgent urination
- blurred vision or vision changes
- yellowing of the skin or eyes
- pain in the upper right part of the stomach
- skin lesions, ulcers, or blisters
- shortness of breath
- difficulty swallowing or breathing
- swelling of the eyes, face, lips, tongue, throat, arms, hands, feet, ankles, or lower legs
Anastrozole can cause or worsen osteoporosis. It can decrease the density of your bones and increase the chance of fractures and broken bones. Talk to your doctor about the risks of taking this medicine and find out what you can do to lower these risks.
Anastrozole may cause other side effects. Call your doctor if you have any unusual problems while taking this medicine.
If you experience a serious side effect, you or your doctor can submit a report online to the Food and Drug Administration’s (FDA) MedWatch Adverse Event Reporting program (http://www.fda.gov/Safety/MedWatch) or by phone (1-800-332-1088).
What should I know about storage and disposal of this medication?
Keep this medicine in the container it came in, tightly closed, and out of the reach of children. Store at room temperature and away from excess heat and moisture (not in the bathroom).
It is important to keep all medicines out of the sight and reach of children, since many containers (such as those containing weekly pills and those for eye drops, creams, patches and inhalers) are not resistant to children and small children can easily open them. To protect young children from poisoning, always close the safety caps and immediately place the medicine in a safe place, one that is upright and out of their sight and reach. http://www.upandaway.org
Unnecessary medications must be disposed of in special ways to ensure they cannot be consumed by pets, children, and others. However, you should not flush this medicine down the toilet. Instead, the best way to dispose of your medications is through a drug take-back program. Talk to your pharmacist or contact your local garbage / recycling department to find out about take-back programs in your community. See the FDA Safe Drug Disposal website (http://goo.gl/c4Rm4p) for more information if you do not have access to a take-back program.
In case of emergency/overdose
In case of overdose, call the poison control helpline at 1-800-222-1222. Information is also available online at https://www.poisonhelp.org/help. If the victim collapsed, had a seizure, is having trouble breathing, or cannot wake up, immediately call 911 for emergency services.
What other information should I know?
Keep all appointments with your doctor and the laboratory. Your doctor may order certain lab tests to check your body’s response to anastrozole.
Do not let anyone else take your medicine. Ask your pharmacist any questions you have about refilling your prescription.
It is important that you keep a written list of all prescription and over-the-counter (over-the-counter) medications you are taking, as well as any products such as vitamins, minerals, or other dietary supplements. You should bring this list with you every time you visit a doctor or if you are admitted to a hospital. It is also important information to take with you in case of emergencies.
Disclaimer: We have made every effort to ensure that all information is factually accurate, comprehensive and up-to-date. However, this article should not be used as a licensed health care professional’s choice of knowledge and expertise. You should always consult your doctor or other health care professional before taking any medication. The information given here is subject to change and it has not been used to cover all possible uses, directions, precautions, warnings, drug interactions, allergic reactions or adverse effects. The lack of warning or other information for any drug does not indicate that the combination of medicine or medication is safe, effective or appropriate for all patients or all specific uses.