Uses
Anastrozole is used to treat breast cancer in women after menopause. Some breast cancers are made to grow faster by a natural hormone called estrogen. Anastrozole decreases the amount of estrogen the body makes and helps to slow or reverse the growth of these breast cancers.
Other Uses
This section contains uses of this drug that are not listed in the approved professional labeling for the drug but that may be prescribed by your health care professional. Use this drug for a condition that is listed in this section only if it has been so prescribed by your health care professional.
This medication may also be used to reduce the chances of breast cancer in high-risk patients.
How To Use
Read the Patient Information Leaflet if available from your pharmacist before you start taking anastrozole and each time you get a refill. If you have any questions, ask your doctor or pharmacist.
Take this medication by mouth with or without food as directed by your doctor, usually once a day.
Use this medication regularly to get the most benefit from it. To help you remember, take it at the same time each day.
Do not increase your dose or use this drug more often or for longer than prescribed. Your condition will not improve any faster, and your risk of serious side effects will increase.
Since this drug can be absorbed through the skin and lungs and may harm an unborn baby, women who are pregnant or who may become pregnant should not handle this medication or breathe the dust from the tablets.
Side Effects
Hot flashes, headache, bone pain, trouble sleeping, dizziness, stomach upset, nausea/vomiting, constipation, diarrhea, loss of appetite, weight gain, tiredness/weakness, increased coughing, or sore throat may occur. If any of these effects last or get worse, tell your doctor or pharmacist promptly.
Remember that this medication has been prescribed because your doctor 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:
- easily broken bones
- pain/swelling of the joint/muscle/tendon
- mental/mood changes (such as depression)
- numb/tingling skin
- swelling hands/ankle/feet
- shortness of breath
- unusual vaginal discharge/bleeding/burning/itching/odor
- pain/redness/swelling of arms or legs
- vision changes
- signs of liver disease (such as nausea/vomiting that doesn't stop, stomach/abdominal pain, yellowing eyes/skin, dark urine)
Get medical help right away if you have any very serious side effects, including:
- chest/jaw/left arm pain
- confusion
- trouble speaking
- weakness on one side of the body
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)
- severe dizziness
- trouble breathing
This is not a complete list of possible side effects. If you notice other effects not listed above, contact your doctor or pharmacist.
In the US -
Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088 or at www.fda.gov/medwatch.
In Canada - Call your doctor for medical advice about side effects. You may report side effects to Health Canada at 1-866-234-2345.
Precautions
Before taking anastrozole, tell your doctor or pharmacist if you are allergic to it; 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:
- heart disease (such as history of heart attack)
- bone loss (osteoporosis)
- liver disease
- high blood pressure
- blood clots
This drug may make you dizzy. Alcohol or marijuana (cannabis) can make you more dizzy. Do not drive, use machinery, or do anything that needs alertness until you can do it safely. Limit alcoholic beverages. Talk to your doctor if you are using marijuana (cannabis).
Before having surgery, tell your doctor or dentist about all the products you use (including prescription drugs, nonprescription drugs, and herbal products).
Since this drug can be absorbed through the skin and lungs and may harm an unborn baby, women who are pregnant or who may become pregnant should not handle this medication or breathe the dust from the tablets.
Anastrozole is used mainly in women after menopause. If you have not gone through menopause, this medication must not be used during pregnancy. It may harm an unborn baby. Discuss the use of reliable forms of birth control (such as latex condoms) while taking this medication and for at least 3 weeks after stopping treatment with your doctor. Products containing estrogen (such as birth control pills) should not be used. 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, breastfeeding is not recommended while using this drug and for at least 2 weeks after the last dose. Consult your doctor before breastfeeding.
Drug Interactions
Drug interactions may change how your medications work or increase your risk for serious side effects. This document does not contain all possible drug interactions. Keep a list of all the products you use (including prescription/nonprescription drugs and herbal products) and share it with your doctor and pharmacist. Do not start, stop, or change the dosage of any medicines without your doctor's approval.
Some products that may interact with this drug are:
- estrogens
- tamoxifen
- tibolone
Overdose
If someone has overdosed and has serious symptoms such as passing out or trouble breathing, call 911. Otherwise, call a poison control center right away. US residents can call their local poison control center at 1-800-222-1222. Alberta residents can call PADIS (Poison and Drug Information Service) 24 hours a day at 1-800-332-1414. Canada residents can call a provincial poison control center.
Notes
Do not share this medication with others.
Lab and/or medical tests (such as cholesterol levels, liver function, bone density) should be done while you are taking this medication. Keep all medical and lab appointments. Consult your doctor for more details.
This medication can increase the risk of bone loss (osteoporosis). Talk with your doctor about your risk, and about available treatments for osteoporosis. Lifestyle changes that reduce the risk of bone loss include doing weight-bearing exercise, getting enough calcium and vitamin D, stopping smoking, and limiting alcohol.
Missed Dose
If you miss a dose, take it as soon as you remember. If it is near the time of the next dose, skip the missed dose. Take your next dose at the regular time. Do not double the dose to catch up.
If you have questions about missing a dose or you don't have more medication, contact your healthcare provider or pharmacist.
Storage
Store at room temperature away from light and moisture. Do not store in the bathroom. Keep all medications away from children and pets.
Do not flush medications down the toilet or pour them into a drain unless instructed to do so. Properly discard this product when it is expired or no longer needed. Consult your pharmacist or local waste disposal company.