Description and Brand Names

Drug information provided by: Micromedex

US Brand Name

  1. Arimidex

Descriptions


Anastrozole is used to treat certain types of breast cancer in women who have already stopped menstruating (postmenopausal). It is also used for women who have already had other cancer treatments (e.g., tamoxifen).

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.

This medicine is available only with your doctor's prescription.

Once a medicine has been approved for marketing for a certain use, experience may show that it is also useful for other medical problems. Although these uses are not included in product labeling, anastrozole is used in certain patients with the following medical conditions:

  • Breast cancer, neoadjuvant treatment for hormone receptor-positive, operable or potentially operable, locally advanced disease in postmenopausal women (treatment for advanced breast cancer that may respond to surgery in women who have already stopped menstruating).

This product is available in the following dosage forms:

  • Tablet

Before Using

In deciding to use a medicine, the risks of taking the medicine must be weighed against the good it will do. This is a decision you and your doctor will make. For this medicine, the following should be considered:

Allergies

Tell your doctor if you have ever had any unusual or allergic reaction to this medicine or any other medicines. Also tell your health care professional if you have any other types of allergies, such as to foods, dyes, preservatives, or animals. For non-prescription products, read the label or package ingredients carefully.

Pediatric

Appropriate studies performed to date have not demonstrated pediatric-specific problems that would limit the usefulness of anastrozole in children.

Geriatric

Appropriate studies performed to date have not demonstrated geriatric-specific problems that would limit the usefulness of anastrozole in the elderly.

Pregnancy

Information about this anastrozole-oral-route
Pregnancy Category Explanation
All Trimesters X Studies in animals or pregnant women have demonstrated positive evidence of fetal abnormalities. This drug should not be used in women who are or may become pregnant because the risk clearly outweighs any possible benefit.

Breastfeeding

There are no adequate studies in women for determining infant risk when using this medication during breastfeeding. Weigh the potential benefits against the potential risks before taking this medication while breastfeeding.

Drug Interactions

Although certain medicines should not be used together at all, in other cases two different medicines may be used together even if an interaction might occur. In these cases, your doctor may want to change the dose, or other precautions may be necessary. When you are taking this medicine, it is especially important that your healthcare professional know if you are taking any of the medicines listed below. The following interactions have been selected on the basis of their potential significance and are not necessarily all-inclusive.

Using this medicine with any of the following medicines may cause an increased risk of certain side effects, but using both drugs may be the best treatment for you. If both medicines are prescribed together, your doctor may change the dose or how often you use one or both of the medicines.

  • Tamoxifen

Other Interactions

Certain medicines should not be used at or around the time of eating food or eating certain types of food since interactions may occur. Using alcohol or tobacco with certain medicines may also cause interactions to occur. Discuss with your healthcare professional the use of your medicine with food, alcohol, or tobacco.

Other Medical Problems

The presence of other medical problems may affect the use of this medicine. Make sure you tell your doctor if you have any other medical problems, especially:

  • Bone problems (osteoporosis) or
  • Hypercholesterolemia (high cholesterol or fat in the blood) or
  • Ischemic heart disease (heart attack, angina), history of, or
  • Liver disease—Use with caution. May make these conditions worse.
  • Premenopausal women (have menstrual cycles)—Should not be used in these patients.

Proper Use

Take this medicine only as directed by your doctor. Do not take more of it, do not take it more often, and do not take it for a longer time than your doctor ordered. To do so may increase the chance for side effects.

You may take this medicine with or without food.

Anastrozole sometimes causes nausea, vomiting, or diarrhea. However, it is very important that you continue to use the medicine, even if you begin to feel ill. Ask your doctor for ways to prevent these effects or make them less severe.

This medicine comes with a patient information leaflet. Read and follow these instructions carefully. Ask your doctor if you have any questions.

Dosing

The dose of this medicine will be different for different patients. Follow your doctor's orders or the directions on the label. The following information includes only the average doses of this medicine. If your dose is different, do not change it unless your doctor tells you to do so.

The amount of medicine that you take depends on the strength of the medicine. Also, the number of doses you take each day, the time allowed between doses, and the length of time you take the medicine depend on the medical problem for which you are using the medicine.

  • For oral dosage form (tablets):
    • For breast cancer:
      • Adults—1 milligram (mg) once a day.
      • Children—Use and dose must be determined by your doctor.

Missed Dose

If you miss a dose of this medicine, take it as soon as possible. However, if it is almost time for your next dose, skip the missed dose and go back to your regular dosing schedule. Do not double doses.

Storage

Store the medicine in a closed container at room temperature, away from heat, moisture, and direct light. Keep from freezing.

Keep out of the reach of children.

Do not keep outdated medicine or medicine no longer needed.

Ask your healthcare professional how you should dispose of any medicine you do not use.

Precautions

It is important that your doctor check your progress at regular visits to make sure that this medicine is working properly. Blood tests may be needed to check for unwanted effects.

It is unlikely that a postmenopausal woman may become pregnant. But, you should know that using this medicine while you are pregnant could harm your unborn baby. Use an effective form of birth control to keep from getting pregnant. If you think you have become pregnant while using the medicine, tell your doctor right away.

This medicine may cause a serious type of allergic reaction called anaphylaxis. Anaphylaxis can be life-threatening and requires immediate medical attention. Call your doctor right away if you have itching; hives; hoarseness; trouble breathing; trouble swallowing; or any swelling of your hands, face, or mouth while you are using this medicine.

This medicine may decrease bone mineral density when used for a long time. A low bone mineral density can cause weak bones or osteoporosis. If you have any questions about this, talk to your doctor.

This medicine may increase your cholesterol or fat in the blood. If this happens, your doctor may give you medicine to lower the cholesterol and fat.

Stop taking this medicine and check with your doctor right away if you start having chest pains or shortness of breath. This medicine may increase the chance of heart attack or stroke in women who have a history of ischemic heart disease.

Side Effects

Along with its needed effects, a medicine may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.

Check with your doctor immediately if any of the following side effects occur:

More common

  1. Blurred vision
  2. chest pain or discomfort
  3. dizziness
  4. headache
  5. nervousness
  6. pounding in the ears
  7. shortness of breath
  8. slow or fast heartbeat
  9. swelling of the feet or lower legs

Less common

  1. Arm, back, or jaw pain
  2. chest tightness or heaviness
  3. cough or hoarseness
  4. difficult or painful urination
  5. dizziness, severe
  6. fever or chills
  7. headache, continuing
  8. increased blood pressure
  9. lower back or side pain
  10. nausea
  11. pain, tenderness, bluish color, or swelling of the foot or leg
  12. sore throat
  13. sudden shortness of breath
  14. sweating
  15. unusual tiredness or weakness
  16. vaginal bleeding (unexpected and heavy)

Incidence not known

  1. Blistering, peeling, or loosening of the skin
  2. hives
  3. itching, puffiness, or swelling of the eyelids or around the eyes, face, lips, or tongue
  4. large, hive-like swelling on the face, eyelids, lips, tongue, throat, hands, legs, feet, or sex organs
  5. red skin lesions, often with a purple center
  6. sores, ulcers, or white spots in the mouth or on the lips
  7. welts

Some side effects may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. Also, your health care professional may be able to tell you about ways to prevent or reduce some of these side effects. Check with your health care professional if any of the following side effects continue or are bothersome or if you have any questions about them:

More common

  1. Acid or sour stomach
  2. back pain
  3. belching
  4. body aches or pain
  5. bone pain
  6. congestion
  7. constipation
  8. decrease in height
  9. diarrhea
  10. dry mouth
  11. dryness or soreness of the throat
  12. feeling of warmth
  13. fever
  14. flushing or redness of the skin, especially on the face and neck
  15. heartburn
  16. hot flashes
  17. increased appetite
  18. indigestion
  19. lack or loss of strength
  20. loss of appetite
  21. mood or mental changes
  22. pain in the back, ribs, arms, or legs
  23. pain, general
  24. pelvic pain
  25. runny nose
  26. skin rash
  27. stomach discomfort, upset, or pain
  28. tender, swollen glands in the neck
  29. trouble in swallowing
  30. voice changes
  31. vomiting
  32. weakness
  33. weight loss

Less common

  1. Anxiety and confusion
  2. breast pain
  3. chills
  4. cough producing mucus
  5. difficulty breathing
  6. dryness of the vagina
  7. general feeling of discomfort or illness
  8. itching of the skin
  9. joint pain and stiffness
  10. loss of hair
  11. muscle pain
  12. numbness or tingling of the hands or feet
  13. shivering
  14. sleepiness or unusual drowsiness
  15. trouble sleeping or sleeplessness
  16. weight gain
  17. wheezing

Other side effects not listed may also occur in some patients. If you notice any other effects, check with your healthcare professional.

Call your doctor for medical advice about side effects. You may report side effects to the FDA at 1-800-FDA-1088.