Like all medicines, betahistine can cause side effects, although not everyone gets them. It's generally a very safe medicine.
Common side effects
These common side effects of betahistine happen in more than 1 in 100 people. They are usually mild and will stop by themselves. There are things you can do to help cope with them:
Feeling sick (nausea)
Take betahistine with or after a meal or snack. It may also help if you do not eat rich or spicy food.
Indigestion (acid reflux)
Take betahistine with or after food. If you get repeated indigestion, contact your doctor as soon as possible. If you need something to ease the discomfort, try taking an antacid, but do not put off going to the doctor.
Bloating or mild stomach ache
Try taking betahistine with or after food.
Headache
Make sure you rest and drink plenty of fluids. Do not drink too much alcohol. You can take an everyday painkiller like paracetamol. Talk to your doctor if headaches last longer than a week or are severe.
Speak to a doctor or pharmacist if the advice on how to cope does not help and a side effect is still bothering you or does not go away.
Serious allergic reaction
In rare cases, it's possible to have a serious allergic reaction (anaphylaxis) to betahistine.
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 betahistine. For a full list, see the leaflet inside your medicine packet.
You can report any suspected side effect using the Yellow Card safety scheme.