About this drug
Fulvestrant is used to treat cancer. It is given by a shot in your muscle and is called an “IM injection."
Possible side effects (more common)
- Nausea and throwing up (vomiting). These symptoms may happen within a few hours your treatment and may last up to several days. Medicines are available to stop or lessen these side effects.
- Abdominal pain
- Back pain
- Redness and soreness at the injection site
Possible side effects (less common)
- Constipation (not able to move bowels)
- Loose bowel movements (diarrhea) that may last for a few days
- Feeling short of breath
- Sore throat
- Changes in your liver function. Your doctor will check your liver function as needed.
Treating side effects
- Vaginal lubricants can be used to lessen vaginal dryness, itching, and pain during sex.
- Ask your doctor or nurse about medicines that are available to help stop or lessen constipation.
- If you are not able to move your bowels, check with your doctor or nurse before you use any enemas, laxatives, or suppositories
- Ask your doctor or nurse about medicine that is available to help stop or lessen nausea, throwing up, loose bowel movements, back pain, or headache.
- 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).
If you are to get fulvestrant by IM shot at home, you will get directions for storing and injecting the drug. Store the syringes in the refrigerator — never freeze them.
Food and drug interactions
There are no known interactions of fulvestrant 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 higher
- Nausea that stops you from eating or drinking
- Throwing up more than 3 times a day
- Severe headache
- Severe stomach pain with nausea and throwing up
- Wheezing or trouble breathing
- Rash or itching
Call your doctor or nurse as soon as possible if any of these symptoms happen:
- Lower belly pain or nausea that is not relieved by prescribed medicines
- No bowel movement for 3 days or if you feel uncomfortable
- Headache or back pain that does not go away
- Throat pain or inability to eat or drink
- Loose bowel movements (diarrhea) more than 4 times a day or diarrhea with weakness or feeling lightheaded.
Sexual problems and reproduction concerns
- Infertility warning: Fulvestrant is usually used in women. Sexual problems and reproduction concerns may happen. In both men and women, this drug may affect your ability to have children. This cannot be determined before your therapy. Talk with your doctor or nurse if you plan to have children. Ask for information on sperm or egg banking.
- In men, this drug may interfere with your ability to make sperm, but it should not change your ability to have sex.
- In women, menstrual bleeding may not be normal for you, or may stop while you are getting this drug. Do not think that you cannot become pregnant if you do not have a menstrual period.
- Women may go through signs of menopause (change of life) like vaginal dryness or itching. Vaginal lubricants can be used to lessen vaginal dryness, itching, and pain during sex.
- Genetic counseling is available for you to talk about the effects of this drug therapy on future pregnancies. Also, a genetic counselor can look at the possible risk of problems in the unborn baby due to this medicine if an exposure happens during pregnancy.
- Pregnancy warning: This drug may have harmful effects on the unborn child, so effective methods of birth control should be used during your cancer treatment.
- Breast feeding warning: It is not known if this drug passes into breast milk. For this reason, women should talk to their doctor about the risks and benefits of breast feeding during treatment with this drug because this drug may enter the breast milk and badly harm a breast feeding baby.
Revised July 2014