Like all medicines, colecalciferol can cause side effects, although not everyone gets them.
Common side effects
There are things you can do to help cope with these common side effects of colecalciferol:
Stomach (gastrointestinal) pain
Speak to your doctor if you have a pain in your stomach.
Feeling sick (nausea)
Try taking your tablets with food. It may also help if you avoid rich or spicy food.
If it carries on, tell your doctor. They may be able to prescribe an extra medicine to protect your stomach.
Headache
Make sure you rest and drink plenty of fluids. Do not drink too much alcohol. Ask your pharmacist to recommend a painkiller.
Speak to a doctor or pharmacist if a side effect continues to bother you, or lasts more than a few days.
Serious side effects
Call your doctor or call 111 if:
- you find that you need to pee more often
- you get swelling in any part of your body
- you get a high temperature and a sharp pain in your side or on one side of your lower back – this could be the early stages of kidney stones
- you are sick (vomit), feel confused, get bone or joint pain, or an irregular heartbeat – these could be signs of too much calcium (hypercalcemia)
Serious allergic reaction
In rare cases, it's possible to have a serious allergic reaction (anaphylaxis) to colecalciferol.
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.
Long-term side effects
Taking too much colecalciferol over a long period of time can cause a skin rash. It can also cause high levels of calcium.
Too much calcium in your body (hypercalcaemia) can cause stomach pain, weaken your bones and damage your kidneys and heart.
Your doctor will arrange a blood test to check your calcium levels. If your test result shows that your calcium levels are high, they may ask you to stop taking colecalciferol until your calcium levels are normal again.
Other side effects
These are not all the side effects of colecalciferol. For a full list, see the leaflet inside your medicine's packet.
You can report any suspected side effect using the Yellow Card safety scheme.