Like all medicines, bimatoprost can cause side effects, but not everyone gets them.
Common side effects of bimatoprost
These common side effects of bimatoprost happen in more than 1 in 100 people. There are things you can do to help cope with them:
Change in eye colour
Bimatoprost eye drops may increase the amount of brown colour in the iris of the eye you're treating. Talk to your doctor before you start using bimatoprost if you're worried about this.
If this happens, you may not notice any change until you have been using the eye drops for several months or years.
This colour change can be permanent and may be more obvious if you're only using the eye drops in one eye.
An itchy or painful eye and a feeling that something's in your eye, blurred vision, or watery eyes
This should go away when your body gets used to bimatoprost, but talk to your doctor or pharmacist if you're worried about this. A cold water compress on the closed eye may help.
If the eye drops irritate your eyes and make them water so much that you think about stopping using the drops, talk to your doctor straight away. They may prescribe something different for you.
Do not drive, cycle, use tools or operate heavy machinery until your eyes feel comfortable again and your vision is clear.
Changes to your eyelashes – growing longer and thicker
If this happens, you may not be able to do anything about it. But your eyelashes would likely return to normal if you ever stop using bimatoprost.
Talk to your pharmacist or doctor if you're worried about this.
Changes to the skin around your eye
You might notice some changes to the skin around your eye. Changes may include red and itchy eyelids, darker skin colour around your eye and hair growth around your eye. Any redness or darkening may be less obvious on brown or black skin.
Try to avoid the eye drop liquid touching your skin too often to reduce the chance of this happening.
These changes are usually mild and may disappear if you ever stop using bimatoprost. Talk to your doctor or pharmacist if you're worried about this.
Changes to your eyelids and the area around your eye
You may lose some of the fat in the area around the eye you're treating. This can lead to your eyelid crease becoming deeper, your eye looking sunken, a drooping eyelid, tighter skin around your eye, and more of the lower white part of your eye showing.
These changes are usually mild and may disappear if you ever stop using bimatoprost. Talk to your doctor or pharmacist if you're worried about this.
Keep using the medicine, but talk to your doctor or pharmacist if the advice on how to cope does not help and these side effects bother you or do not go away.
Serious side effects
Serious side effects are rare and may affect 1 in 1,000 people.
Do not use any more bimatoprost if you get serious side effects.
Call a doctor or call 111 now if you:
- have breathing problems
- have asthma or COPD and your breathing gets worse
Immediate action required: Call 999 or go to A&E if you:
- have severe breathing problems
- feel faint or pass out
Do not drive to A&E. Ask someone to drive you or call 999 and ask for an ambulance.
Bring all the medicines you take with you.
Serious allergic reaction
In rare cases, it's possible to have a serious allergic reaction (anaphylaxis) to bimatoprost.
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.
Do not drive yourself to A&E.
The person you speak to at 999 will give you advice about what to do.
Other side effects
These are not all the side effects of bimatoprost. For a full list see the leaflet inside your medicine packet.
You can report any suspected side effect using the Yellow Card safety scheme.