Common side effects
Like all medicines, simvastatin can cause side effects in some people, but not everybody gets them.
Talk to your doctor or pharmacist if you do get any side effects and they bother you, or do not go away. They may recommend trying a lower dose of simvastatin, or a different statin.
Serious side effects
It happens rarely, but less than 1 in 1,000 people taking simvastatin may have a serious side effect.
Stop taking simvastatin and call a doctor or call 111 now if:
- you get unexplained muscle pain, tenderness, weakness or cramps (this is more likely if you’re taking a higher dose of simvastatin, and it can happen a few weeks or months after you first start taking this medicine) – this can be signs of muscle breakdown and kidney damage
- the whites of your eyes turn yellow, or your skin turns yellow (although this may be less obvious on brown or black skin), or if you have pale poo and dark pee – this can be signs of liver problems
- you get a skin rash with pink-red blotches, especially on the palms of your hands or soles of your feet – this could be a sign of the skin reaction, erythema multiforme
- you have severe stomach pain – this can be a sign of acute pancreatitis
- you have a cough, feel short of breath, and have lost weight – this can be a sign of lung disease
- you have a weakness in your arms or legs that gets worse after activity, or if you get double vision, drooping eyelids, problems swallowing or shortness of breath – these can be a sign of myasthenia gravis
Urgent advice: Call 999 now or go to A&E if:
- you develop severe breathing or swallowing problems
Serious allergic reaction
In rare cases, it’s possible to have a serious allergic reaction (anaphylaxis) to simvastatin.
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 simvastatin. For a full list see the leaflet inside your medicines packet.
You can report any suspected side effect using the Yellow Card safety scheme.