Anastrozole Oral: Uses, Side Effects, Interactions

What is anastrozole?

Anastrozole is used to treat early hormone receptor-positive breast cancer. It is also used for first-line treatment of hormone receptor-positive or hormone receptor-unknown advanced or metastatic (cancer that has spread) breast cancer. Anastrozole is also used to treat advanced breast cancer that has grown or spread after tamoxifen treatment.
Many breast cancer tumors grow in response to estrogen. This medicine interferes with the production of estrogen in the body. As a result, the amount of estrogen that the tumor is exposed to is reduced, limiting the growth of the tumor.

How to Take Anastrozole

Anastrozole is a tablet that is taken by mouth. You can take this medication with or without food. Do not crush, break or chew the tablet. Your health care team will tell you how much medication you should take. If you miss a dose or vomit after taking your dose, do not take an additional dose. Wait to take your next dose at the scheduled time. Do not take two doses at the same time. Do not stop taking anastrozole without talking to your healthcare team.
It is important to make sure you are taking the correct amount of medication every time. Before every dose, check that what you are taking matches what you have been prescribed. If you take too much medication, notify your health care team or go to the emergency room immediately.
The blood levels of this medication can be affected by certain foods and medications, so they should be avoided. Be sure to tell your healthcare provider about all medications and supplements you take. You should not take this medication if you are currently taking tamoxifen or other medications that include estrogen, including hormone replacement therapy, birth control pills, estrogen creams, vaginal ring and vaginal suppositories.

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 medication may be prescribed for other uses; ask your doctor or pharmacist for more information.

Before taking anastrozole,

tell your doctor and pharmacist if you are allergic to anastrozole, or 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: medications that contain estrogen 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 carefully for side effects.


tell your doctor if you have or have ever had high cholesterol, osteoporosis (condition in which the bones are fragile and break easily), liver, or heart disease.


you should know that anastrozole should only be taken by women who have undergone menopause and cannot become pregnant. However, if you are pregnant or breast-feeding, you should tell your doctor before you begin taking this medication. Anastrozole may harm the fetus.

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:

weakness
headache
hot flashes
sweating
stomach pain
nausea
vomiting
loss of appetite
constipation
diarrhea
heartburn
weight gain
joint, bone, or muscle pain
breast pain
mood changes
depression
difficulty falling asleep or staying asleep
nervousness
dizziness
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
rash
hives
itching
shortness of breath
difficulty swallowing or breathing
swelling of the eyes, face, lips, tongue, throat, arms, hands, feet, ankles, or lower legs


Anastrozole may cause or worsen osteoporosis. It can decrease the density of your bones and increase the chance of broken bones and fractures. Talk to your doctor about the risks of taking this medication and to find out what you can do to decrease these risks.
Anastrozole may cause other side effects. Call your doctor if you have any unusual problems while taking this medication.

Before taking this medicine

Anastrozole is not approved for use in men or children.
You should not take anastrozole if you also take tamoxifen.

Tell your doctor if you have ever had:

heart problems;
coronary artery disease (clogged artery disease);
high cholesterol; or
osteoporosis or low bone mineral density.
Hormonal cancer treatment can weaken your bones. You may be more likely to have a broken bone while using anastrozole. Talk with your doctor about ways to keep your bones healthy.

Dose

The usual dose of anastrozole is 1 tablet (1 milligram) once a day.
Anastrozole is a long-term treatment; you may have to take it for several years.
Always take your anastrozole exactly as your doctor has told you. The pharmacy label on your medicine will tell you how much to take, how often to take it, and any special instructions.

How to take anastrozole

Take anastrozole at the same time each day, either in the morning or the evening. 
You can take anastrozole with or without food.
It is not harmful if you miss a dose of anastrozole. If you forget to take your dose, take it as soon as you remember. But, if it is nearly time for your next dose, just take the next dose at the right time. Do not take double the dose.
Do not stop taking anastrozole suddenly; speak to your doctor before stopping.

Precautions before starting anastrozole

Are you still having menstrual periods? If you have not gone through the menopause you should not take anastrozole
Do you have osteoporosis (a condition that causes your bones to be thinner and weaker than normal)?
Do you have problems with your liver or kidneys?
Are you taking any other medicines, including medicines you can buy without a prescription, such as herbal and complementary medicines?
If any of these apply, it’s important that you tell your doctor or pharmacist before you start anastrozole. Sometimes a medicine isn’t suitable for a person with certain conditions, or it can only be used with extra care.

Further information

Remember, keep this and all other medicines out of the reach of children, never share your medicines with others, and use this medication only for the indication prescribed.
Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.

What is anastrozole? Anastrozole is used to treat early hormone receptor-positive breast cancer. It is also used for first-line treatment of hormone receptor-positive or hormone receptor-unknown advanced or metastatic (cancer that has spread) breast cancer. Anastrozole is also used to treat advanced breast cancer that has grown or spread after…