About This Drug
Anastrozole is used to treat cancer. This drug is given by mouth.
Possible Side Effects (More Common)
- Feeling very tired
- Nausea and throwing up (vomiting). Medicines are available to stop or lessen these side effects.
- Hot flashes
- Muscle weakness
- Back pain
- Bone pain
- Osteoporosis (weak or brittle bones)
Possible Side Effects (Less Common)
- Loose bowel movements (diarrhea)
- Trouble catching your breath
- Swelling of the ankles
Allergic reactions, including anaphylaxis are rare but may happen in some patients. Signs of allergic reactions to this drug may be swelling of the face, feeling like your tongue or throat are swelling, trouble breathing, rash, itching, fever, chills, feeling dizzy, and/or feeling that your heart is beating in a fast or not normal way. Do not take more doses of this drug. You should get urgent medical treatment.
Treating Side Effects
- Ask your doctor or nurse about medicine that is available to help stop or lessen nausea and vomiting.
- Drink 6-8 cups of fluids each day unless your doctor has told you to limit your fluid intake due to some other health problem. A cup is 8 ounces of fluid. If you throw up or have loose bowel movements you should drink more fluids so that you do not become dehydrated (lack water in the body due to losing too much fluid).
- Swallow the medicine whole. Do not chew, break or crush it.
- You can take the medicine with or without food. If you have nausea, take it with food.
- Missed dose: If you miss a dose, take it as soon as you remember. If it is close to your next dose (within 12 hours), skip the missed dose and take the next dose at your normal time. Do not take more than 1 dose at a time. Do not take extra doses.
- Your bone density and lipid panel may be checked while on this medication. Talk about this with your doctor.
Food and Drug Interactions
There are no known interactions of anastrazole with food. This drug may interact with other medicines. Tell your doctor and pharmacist about all the medicines and dietary supplements (vitamins, minerals, herbs and others) that you are taking at this time. The safety and use of dietary supplements and alternative diets are often not known. Using these might affect your cancer or interfere with your treatment. Until more is known, you should not use dietary supplements or alternative diets without your cancer doctor's help.
When to Call the Doctor
Call your doctor or nurse right away if you have any of these symptoms:
- Fever of 100.5 F (38 C) or above
- Bleeding or bruising that is not usual
- Wheezing or trouble breathing
- Rash or itching
- Feeling dizzy or lightheaded
- Feeling that your heart is beating in a fast or not normal way (palpitations)
- Loose bowel movements (diarrhea) more than 4 times a day or diarrhea with weakness or feeling lightheaded
- Blurred vision or other changes in eyesight
- Pain when passing urine; blood in urine
- Pain in your lower back or side
- Confusion or agitation
- Nausea that stops you from eating or drinking
- Throwing up more than 3 times a day
- Chest pain or symptoms of a heart attack. Most heart attacks involve pain in the center of the chest that lasts more than a few minutes. The pain may go away and come back. It can feel like pressure, squeezing, fullness, or pain. Sometimes pain is felt in one or both arms, the back, neck, jaw, or stomach. If any of these symptoms last 2 minutes, call 911.
- Symptoms of a stroke such as sudden numbness or weakness of your face, arm, or leg, mostly on one side of your body; sudden confusion, trouble speaking or understanding; sudden trouble seeing in one or both eyes; sudden trouble walking, feeling dizzy, loss of balance or coordination; or sudden, bad headache with no known cause. If you have any of these symptoms for 2 minutes, call 911.
- Signs of liver problems: dark urine, pale bowel movements, bad stomach pain, feeling very tired or weak, unusual itching, or yellowing of the eyes or skin.
Call your doctor or nurse as soon as possible if any of these symptoms happen:
- Change in hearing, ringing in the ears
- Decreased urine
- Unusual thirst or passing urine often
- Painful mouth or throat that makes it hard to eat or drink
- Nausea not relieved by prescribed medicines
- Rash that is not relieved by prescribed medicines
- Heavy menstrual period lasting longer than normal
- Numbness, tingling, decreased feeling or weakness in fingers, toes, arms, or legs
- Trouble walking or changes in the way you walk, clumsiness in buttoning clothes, opening jars, or other routine hand motions
- Swelling of legs, ankles, or feet
- Weight gain of 5 pounds in one week (fluid retention)
- Lasting loss of appetite or rapid weight loss of five pounds in a week
- Fatigue that interferes with your daily activities
- Headache that does not go away
- Painful, red, or swollen areas on your hands or feet.
- No bowel movement for 3 days or you feel uncomfortable
- Extreme weakness that interferes with normal activities
Revised - August 2014
- Pregnancy warning: This drug is not to be used during pregnancy (used in post-menopausal women only)