Common questions about colecalciferol - Brand names: Lamberts, Hux D3, Solgar, SunVit D3

Colecalciferol is a natural form of vitamin D inside the body. It gets converted to a form of vitamin D your body can use called calcitriol through the liver and the kidneys.

It helps your body to take in more calcium and phosphorous from the food you eat and by getting your kidneys to keep more calcium in the body instead of peeing it out. All types of vitamin D work in this way.

Having the right amount of calcium and phosphorus is important for building your bones and keeping them strong.

Colecalciferol needs to change into its active form (calcitriol) before it can work, so it does not work straight away.

Higher doses of colecalciferol work more quickly. They are taken for a short period of time so have to work more quickly to raise your vitamin D levels.

If you've been getting bone, muscle or joint pain, your symptoms are likely to get better when your vitamin D levels are normal again. This is usually after a few weeks or months.

If your symptoms last longer than this, your doctor may give you a blood test for vitamin D deficiency.

There are different types of vitamin D. These include alfacalcidol, calcitriol and ergocalciferol.

They all work in the same way to regulate the amount of calcium and phosphorous in the body but some work more quickly than others. Your doctor will decide which type of vitamin D to recommend or prescribe depending on your condition.

Calcitriol is a natural form of vitamin D. Your body can use it right away and it works directly to increase the amount of calcium and phosphate in your body. It's used to treat and prevent changes in bones caused by chronic kidney disease (CKD) and for osteoporosis after the menopause.

Alfacalcidol is quickly turned into calcitriol by the liver. It does not need your kidneys to turn it into calcitriol, so it works more quickly than some other forms of vitamin D such as colecalciferol. It can be useful for conditions like chronic kidney disease (CKD).

Colecalciferol and ergocalciferol need your liver and your kidneys to turn them into calcitriol. They work more slowly than alfacalcidol and calcitriol.

Most vitamin D that you can buy is either colecalciferol or ergocalciferol. They are commonly used as daily supplements to prevent vitamin D deficiency in people who cannot get enough vitamin D naturally.

Colecalciferol will not stop any type of contraception from working, including the combined pill and emergency contraception.

Colecalciferol should not affect your ability to drive or ride a bike.

You can drink alcohol if you are taking colecalciferol.

There are no foods or drinks that you need to avoid while taking colecalciferol.

Most people are able to make all the vitamin D they need from sunlight. The body creates vitamin D from direct sunlight on the skin when outdoors.

But we do not always make enough vitamin D from sunlight, so eating foods that are rich in vitamin D can help. You can increase your levels by eating more:

• oily fish – such as salmon, sardines, herring and mackerel
• red meat
• liver
• egg yolks
• fortified foods – such as some fat spreads and breakfast cereals

Everyone should consider taking vitamin D supplements, particularly in autumn and winter. If you are at risk of vitamin D deficiency, however, it's important to take it all year round to help prevent your levels from becoming too low.

You may be at higher risk of vitamin D deficiency if you:

• are aged 65 years or older
• have low or no exposure to the sun, for example if you cover your skin when outside, or are housebound or indoors for long periods
• have brown or black skin
• have a malabsorption disorder
• have had weight loss surgery
• have severe liver disease or end-stage chronic kidney disease
• take certain medicines that can affect your vitamin D levels
• are pregnant or breastfeeding
• have been advised by your doctor to lose weight

If your child has rickets, long-term lifestyle changes will help to prevent them becoming unwell again and keep them healthy.