Like all medicines, tibolone may cause side effects. But it's common to have no side effects or only minor ones.
Side effects often improve as your body gets used to the medicine.
Common side effects
These common side effects of tibolone happen in more than 1 in 100 people. There are things you can do to help cope with them:
Breast tenderness
This usually improves after 4 to 6 weeks as your body gets used to the medicine.
Speak to a doctor if it lasts longer than this or is very painful. You may need to switch to a different type of HRT.
If you notice a lump or changes in your breasts after a few months of taking tibolone, contact your doctor for advice.
Stomach pain or pelvic pain
Try to rest and relax. It can help to eat and drink slowly and have smaller and more frequent meals. Putting a heat pad or covered hot water bottle on your stomach may also help.
If you're in a lot of pain, speak to your pharmacist or doctor.
Unusual hair growth
If this bothers you, talk to your doctor about whether another type of HRT might be more suitable.
A pharmacist can also advise on products to remove unwanted hair.
Vaginal bleeding or spotting
Do not use perfumed soaps or washes around your vagina.
If you have thrush, ask a pharmacist to recommend a medicine, or speak to your doctor.
These symptoms should get better after a month or two. Speak to your doctor if they do not improve or they get worse, as you may need to change to a different type of HRT.
Putting on weight
Tibolone can sometimes cause weight gain. However it's also common to put on weight around the time of the menopause and as you get older, so it might not be your medicine that's causing it.
Eating a healthy, balanced diet and regular exercise will help you keep to a healthy weight.
Speak to a pharmacist or doctor if the advice on how to cope does not help and a side effect is still bothering you or does not go away.
Serious side effects
Call a doctor or call 111 straight away if any of these rare but serious side effects happen to you:
- the whites of your eyes turn yellow, or your skin turns yellow, although this may be less obvious on brown or black skin – this could be a sign of liver problems
- you suddenly have a migraine-type headache or severe headache
- you get pain, redness or swelling in one of your legs, usually in your calf – this could be a sign of a blood clot or deep vein thrombosis (DVT)
Speak to a GP if:
- you have a lump or changes in your breasts, especially dimpling of the skin, changes in the nipple or any lumps you can see or feel – this could be a sign of breast cancer
- you get continued vaginal bleeding or any changes in vaginal bleeding after you've been taking tibolone for more than 6 months – this could be a sign of womb cancer
It's important to attend your breast screening (mammogram) appointments while you're taking HRT.
Immediate action required: Call 999 or go to A&E now if:
- you have pain in your chest and breathlessness – this could be a sign of a blood clot in your lungs (pulmonary embolism) or heart problems
- you have difficulty speaking or moving your arm or leg, or your face has dropped on one side – this could be a sign of a stroke
Serious allergic reaction
In rare cases, it's possible to have a serious allergic reaction (anaphylaxis) to tibolone.
Immediate action required: Call 999 now if:
- your lips, mouth, throat or tongue suddenly become swollen
- you're breathing very fast or struggling to breathe (you may become very wheezy or feel like you're choking or gasping for air)
- your throat feels tight or you're struggling to swallow
- your skin, tongue or lips turn blue, grey or pale (if you have black or brown skin, this may be easier to see on the palms of your hands or soles of your feet)
- you suddenly become very confused, drowsy or dizzy
- someone faints and cannot be woken up
- a child is limp, floppy or not responding like they normally do (their head may fall to the side, backwards or forwards, or they may find it difficult to lift their head or focus on your face)
You or the person who's unwell may also have a rash that's swollen, raised, itchy, blistered or peeling.
These can be signs of a serious allergic reaction and may need immediate treatment in hospital.
Other side effects
These are not all the side effects of tibolone. For a full list see the leaflet inside your medicines packet.
You can report any suspected side effect using the Yellow Card safety scheme.