Like any medicine, the hormones used in hormone replacement therapy (HRT) can cause side effects.
Any side effects usually improve over time, so it's a good idea to persevere with treatment for at least 3 months if possible.
Speak to a GP if you have severe side effects or they continue for longer than 3 months.
Side effects of oestrogen
The main side effects of taking oestrogen include:
- bloating
- breast tenderness or swelling
- swelling in other parts of the body
- feeling sick
- leg cramps
- headaches
- indigestion
- vaginal bleeding
These side effects will often pass after a few weeks. To ease side effects, try:
- taking your oestrogen dose with food, which may help feelings of sickness and indigestion
- eating a low-fat, high-carbohydrate diet, which may reduce breast tenderness
- doing regular exercise and stretching, to help leg cramps
If side effects persist, your GP may recommend switching to a different way of taking oestrogen (for example, changing from a tablet to a patch), changing the medicine you're taking, or lowering your dose.
Side effects of progestogen
The main side effects of taking progestogen include:
- breast tenderness
- swelling in other parts of the body
- headaches or migraines
- mood swings
- depression
- acne
- tummy (abdominal) pain
- back pain
- vaginal bleeding
As with side effects of oestrogen, these will usually pass after a few weeks.
If they persist, a GP may recommend switching to a different way of taking progestogen, changing the medicine you're taking, or lowering your dose.
Weight gain and HRT
Many women believe that taking HRT will make them put on weight, but there's no evidence to support this claim.
You may gain some weight during the menopause, but this often happens regardless of whether you take HRT.
Exercising regularly and eating a healthy diet should help you to lose any unwanted weight.
More serious risks
HRT has also been associated with an increased risk of blood clots and certain types of cancer.
Find out more about the risks of HRT
Reporting side effects
The Yellow Card Scheme allows you to report suspected side effects from any type of medicine you are taking.
It's run by a medicines safety watchdog called the Medicines and Healthcare products Regulatory Agency (MHRA).
Page last reviewed: 09 September 2019
Next review due: 09 September 2022