- Hot flushes.
- Night sweats.
- Vaginal dryness or irritation.
- Loss of sex drive.
- Indigestion or mild nausea.
- Periods become irregular or lighter.
- Periods may stop while taking tamoxifen, often because the menopause had occurred naturally or other treatments such as chemotherapy have caused an earlier menopause.
- A decrease in the strength of the bones in pre-menopausal women (this is not thought to affect post-menopausal women taking tamoxifen). See Osteoporosis booklet.
- Less common side effects
Because of the risk of blood clots, it is especially important to tell your GP if you have any symptoms such as a swelling or pain in your leg or a feeling of shortness of breath.
- Eye-sight problems.
- Hair thinning.
- Increased risk of blood clots (although the overall risk remains low).
It's important to tell your GP or specialist if you have any unexpected vaginal bleeding, discharge or pain.
- Thickening of the lining of the womb
- Polyps, ovarian cysts or, very rarely, cancer of the womb
Common side effects
- You may develop a skin reaction during or after radiotherapy to your breast, including redness, darkening, tenderness or itching of the skin. This will tend to begin 10 to 14 days after starting treatment. Your skin may peel or flake as treatment goes on, and there may be a red, sore, moist reaction.
- You may have aches, twinges or shooting pains in the breast area. These are usually mild, but can go on for some time after treatment is finished.
- If the treatment area includes the central part of the chest, a small area of the oesophagus (gullet) can be affected, causing heartburn and discomfort. You may also experience loss of appetite and sometimes nausea.
Less common side effects
- Radiotherapy to the breast and armpit can cause tissue hardening. This is known as fibrosis and is caused by a build-up of scar tissue.
- Sometimes part of the lung behind the treatment area can become inflamed, causing a dry cough or shortness of breath. This usually heals by itself.