Facts about Tamoxifen side effects

Tamoxifen side effects :
a look at Purpose, Use and Impact

Tamoxifen is used to treat breast cancer and to reduce the risk of breast cancer in women at high risk for the disease. Tamoxifen is in a class of drugs known as antiestrogens; it blocks the activity of estrogen, a female hormone produced by the body in the breast. The length of treatment depends on the types of drugs you are taking, how well your body responds to them, and the type of cancer you have.

Tamoxifen is also used sometimes to induce ovulation (egg production) in women who do not produce ova (eggs) but wish to become pregnant, to treat breast pain, and to decrease the size and pain of gynecomastia (swelling and tenderness of the breast). Tamoxifen may be useful in in treating carcinoid tumors. Talk to your doctor about the possible risks of using this drug.

Special Warning about Tamoxifen side effects

According to The American Society of Health-System Pharmacists (ASHP),"Tamoxifen may cause uterine cancer, strokes, and blood clots in the lungs. Tell your doctor if you have ever had a blood clot in the lungs or legs, a stroke, or a heart attack. If you experience any of the following symptoms, call your doctor immediately: abnormal vaginal bleeding, irregular menstrual periods, changes in vaginal discharge, or pelvic pain or pressure. Talk to your doctor about the risks of taking tamoxifen to reduce the risk of developing breast cancer. In women who do have breast cancer, the benefits of tamoxifen outweigh the risks."

Tamoxifen side effects and interactions

It is very important that your doctor check your progress at regular visits to make sure that this medicine is working properly and to check for unwanted Tamoxifen side effects.

A woman should contact her healthcare profession right away if she develops:

  • Changes in vaginal discharge or
  • Changes in vision
  • Coughing up blood
  • Leg swelling or tenderness
  • Menstrual irregularities
  • New breast lumps
  • Pelvic pain or pressure
  • Sudden chest pain
  • Unexplained shortness of breath
  • Vaginal bleeding

If you seek medical attention for any reason, be sure to tell your healthcare professional that you take tamoxifen or have taken tamoxifen.

Tamoxifen side effects may make you more fertile. It is best to use some type of birth control while you are taking it. However, do not use oral contraceptives since they may change the effects of tamoxifen. Tell your doctor right away if you think you have become pregnant while taking this medicine.

Observed Tamoxifen side effects

Along with its needed effects, there may be unwanted Tamoxifen side effects. Although not all of these side effects may occur, if they do occur they may need medical attention. Some side effects will have signs or symptoms that you can see or feel. Your doctor will watch for others by doing certain tests.

Also, because of the way this medicine acts on the body, there is a chance that it might cause other unwanted Tamoxifen side effects that may not occur until months or years after the medicine is used. Tamoxifen increases the chance of cancer of the uterus (womb) in some women taking it. Tamoxifen may cause blockages to form in a vein, lung, or brain. In women, tamoxifen may cause cancer or other problems of the uterus (womb). It also causes liver cancer in rats. In addition, tamoxifen has been reported to cause cataracts and other eye problems. Discuss these possible effects with your doctor.

Check with your doctor as soon as possible if any of the following Tamoxifen side effects occur:

Less Commonly Observed (for both females and males)

Anxiety; blistering, peeling, or loosening of skin and mucous membranes; blurred vision; chest pain; confusion; cough; dizziness; fainting; fast heartbeat; lightheadedness; pain or swelling in legs; shortness of breath or trouble breathing; weakness or sleepiness; yellow eyes or skin ; cataracts in the eyes or other eye problems; liver problems.

Less Commonly Observed (For females only)

Change in vaginal discharge; chills ; fever; hoarseness; lower back or side pain; pain or feeling of pressure in pelvis; pain, redness, or swelling in your arm or leg; painful or difficult urination ; rapid shallow breathing; skin rash or itching over the entire body; sweating ; vaginal bleeding; wheezing.

Other Tamoxifen 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:

Less Commonly Observed (for both females and males)

Bone pain; headache; nausea and/or vomiting (mild); skin rash or dryness.

More Commonly Observed (For females only)

Absent, missed, or irregular periods; confusion; decrease in amount of urine; feeling of warmth redness of the face, neck, arms and occasionally, upper chest; lower back or side pain; menstrual changes; nausea; noisy, rattling breathing; painful or difficult urination; rapid, shallow breathing; skin changes; stopping of menstrual bleeding; swelling of fingers, hands, feet, or lower legs; troubled breathing at rest; vaginal bleeding; weight gain; weight loss; white or brownish vaginal discharge.

Less Commonly Observed (For females only)

Abdominal cramps; black, tarry stools ; bleeding gums; blood in urine or stools; Bluish color changes in skin color ; discouragement; feeling sad or empty; irritability; itching in genital area; lack of appetite; loss of interest or pleasure; pain; pinpoint red spots on skin; stomach or pelvic discomfort, aching or heaviness; swelling ; trouble concentrating; trouble sleeping; unusual bleeding or bruising.

Less Commonly Observed (For males only)

Decreased interest in sexual intercourse; inability to have or keep an erection; loss in sexual ability, desire, drive, or performance.

This medicine may infrequently cause hair thinning or partial loss of hair.

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

Sources : The American Society of Health-System Pharmacists (ASHP) and the United States Pharmacopeia (USP)

There are alternatives to enduring Tamoxifen side effects.
More information here.


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