Colecalciferol is a form of vitamin D. It helps your body to take in more calcium and phosphorous from the food you eat, and helps your kidneys to keep more calcium instead of peeing it out.
We usually get our vitamin D through exposure to sunlight and our diet. Not having enough vitamin D in your body can lead to bone conditions such as rickets and osteomalacia in children, and osteoporosis (thinning of the bones) in adults.
Long-term vitamin D deficiency can cause bone loss, muscle weakness, falls and fractures in older people.
Everyone can benefit from taking colecalciferol as a daily vitamin D supplement. Adults who are not at risk of vitamin D deficiency should consider taking a daily supplement of 10 micrograms (mcg) of vitamin D during autumn and winter.
Adults who are at risk of vitamin D deficiency should take a daily supplement of 10 micrograms of vitamin D, throughout the year.
It is recommended that you take vitamin D if you have a deficiency, or to prevent a deficiency if you:
- are not often outdoors, for example if you're housebound or in an institution, like a care home
- are pregnant or breastfeeding
- usually wear clothes that cover up most of your skin when you're outside
- have dark skin – darker skin may not make enough vitamin D from sunlight
- are 1 to 4 years old or a baby that is breastfed or having less than 500ml of infant formula a day
Vitamin D deficiency is the most common cause of rickets so if your child has low vitamin D levels, your doctor may prescribe colecalciferol for them.
To find out if you have low vitamin D levels, your doctor will give you a blood test. If your levels are severely low, they may prescribe a loading dose course of vitamin D. This is a high strength dose that is only available on prescription.
If your vitamin D levels are OK, or you want to prevent deficiency, you can buy lower dose colecalciferol from pharmacies and shops.
Colecalciferol comes as chewable, dissolvable (soluble) and melt-in-the-mouth (orodispersible) tablets, capsules, a syrup, and oral drops.
There is also a type of vitamin D called calcipotriol, which sounds similar to colecalciferol. Calcipotriol is used to treat the skin condition caused by plaque psoriasis.
Key facts
- Taking low doses of colecalciferol daily is safe and does not normally cause side effects.
- Taking too much colecalciferol can cause calcium and phosphate to build up in your body (hypercalcaemia).
- It may take a few weeks or months to raise your vitamin D levels after a loading dose and you may not feel any different. You'll usually take a blood test 1 month after starting your treatment and then again after 3 to 6 months to check your levels.
- Most of your vitamin D comes from exposure to sunlight but you can also get it from your diet by eating more oily fish and foods with added nutrients.
- There are many different brands of colecalciferol. Other brand names include Hux D3, Lamberts, Pro D3, Solgar and SunVit.