What's the D-eal with Vitamin D?

By Lacy Ternes, PharmD

Low vitamin D levels or "vitamin D deficiency" is defined as a total vitamin D level less than 20 ng/mL. This is very common after transplantation. Why is that? In an effort to prevent skin cancer, transplant recipients are advised to avoid or protect themselves from the sun – the body's major source of vitamin D. This leaves transplant recipients at risk for low levels of vitamin D because very few foods naturally contain vitamin D. Additionally, some medications taken after transplantation, such as prednisone, can reduce vitamin D levels in your body. It is strongly encouraged that all transplant recipients are screened for vitamin D deficiency. Although each transplant center is unique, if you have not had your total vitamin D level checked, you are encouraged to talk to your healthcare provider(s).

What are the consequences of Vitamin D deficiency?
Vitamin D deficiency can impact the health of your bones by leading to abnormalities in calcium, phosphorus, and bone metabolism. Muscle weakness may also occur if you are vitamin D deficient. The combination of reduced bone health and muscle weakness can increase your risk of falling and breaking bones.

What products are available for Vitamin D deficiency?
Vitamin D is available as both prescription and over-the-counter products. The prescription products are only available as vitamin D2, also known as ergocalciferol. Over-the-counter (OTC) products may be available as either vitamin D3, also known as cholecalciferol, or vitamin D2. The table below is a general list of available products and their corresponding vitamin D content. The type of product or "source" that you take is not as important as ensuring that you are taking an amount sufficient to achieve your goal total vitamin D level, which takes into account both vitamin D2 and vitamin D3.

**If you are taking a combination product of calcium plus vitamin D, don't forget to include the amount of vitamin D in your combined product along with your stand-alone vitamin D supplement for your total daily vitamin D intake.**

Vitamin D products

Vitamin D SourceVitamin D content
Prescription products available in the United States
Vitamin D2 (ergocalciferol)50,000 IU per capsule
Drisdol (vitamin D2) liquid8,000 IU per milliliter
Supplemental Sources
Multivitamin400, 500, or 1,000 IU vitamin D2 or vitamin D3
Vitamin D3400, 800, 1000, 2000, 5000, 10,000, or 50,000 IU
IU = international unit

How should you take Vitamin D?
Vitamin D can be taken on an empty stomach or with a meal. How frequently it is taken will be determined on your needs to achieve and maintain your goal vitamin D level.

Achieving your goal Vitamin D level:
A total vitamin D level greater than 30 ng/mL is often considered an appropriate goal; however, this number may vary depending on your individual needs and should be discussed with your healthcare provider(s). To treat vitamin D deficiency there are a variety of treatment regimens. Adults are commonly prescribed ergocalciferol 50,000 IU to be taken once a week for 8 weeks, followed by a re-check of their total vitamin D level. Once you achieve your goal level using the prescribed ergocalciferol often you will be advised to take an OTC product to maintain adequate vitamin D levels. The amount of vitamin D you take in an OTC product will depend on your needs, but commonly is in the range of 1000-2000 IU per day. After achieving your vitamin D goal, the frequency by which you will need to get your vitamin D levels re-checked will vary based on your healthcare provider. Obtaining a yearly level is common.

What are the benefits and safety issues associated with Vitamin D?
For adults, the benefits of vitamin D levels within the target range include the maintenance of healthy bones and reducing your chance of falling or braking bones. Although taking vitamin D is considered safe, how much you take should be determined based on your individual needs and the recommendations of your healthcare provider. Vitamin D may cause some people to develop high calcium levels in the blood and/or urine and should be monitored. Before you start a vitamin D supplement, talk with your healthcare provider to make sure vitamin D is safe and beneficial for you.


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