Description and Brand Names

Drug information provided by: Merative, Micromedex®

US Brand Name

  1. Calciferol
  2. Delta D3
  3. DHT
  4. DHT Intensol
  5. Drisdol
  6. Hectorol
  7. Rayaldee
  8. Rocaltrol
  9. Vitamin D
  10. Zemplar

Canadian Brand Name

  1. D-Vi-Sol
  2. Radiostol Forte


Vitamins are compounds that you must have for growth and health. They are needed in small amounts only and are available in the foods that you eat. Vitamin D is necessary for strong bones and teeth.

Lack of vitamin D may lead to a condition called rickets, especially in children, in which bones and teeth are weak. In adults it may cause a condition called osteomalacia, in which calcium is lost from bones so that they become weak. Your doctor may treat these problems by prescribing vitamin D for you. Vitamin D is also sometimes used to treat other diseases in which calcium is not used properly by the body.

Ergocalciferol is the form of vitamin D used in vitamin supplements.

Some conditions may increase your need for vitamin D. These include:

  • Alcoholism
  • Intestine diseases
  • Kidney disease
  • Liver disease
  • Overactivity of the parathyroid glands with kidney failure
  • Pancreas disease
  • Surgical removal of stomach

In addition, individuals and breast-fed infants who lack exposure to sunlight, as well as dark-skinned individuals, may be more likely to have a vitamin D deficiency. Increased need for vitamin D should be determined by your health care professional.

Alfacalcidol, calcifediol, calcitriol, and dihydrotachysterol are forms of vitamin D used to treat hypocalcemia (not enough calcium in the blood). Alfacalcidol, calcifediol, and calcitriol are also used to treat certain types of bone disease that may occur with kidney disease in patients who are undergoing kidney dialysis.

Claims that vitamin D is effective for treatment of arthritis and prevention of nearsightedness or nerve problems have not been proven. Some psoriasis patients may benefit from vitamin D supplements; however, controlled studies have not been performed.

Injectable vitamin D is given by or under the supervision of a health care professional. Some strengths of ergocalciferol and all strengths of alfacalcidol, calcifediol, calcitriol, and dihydrotachysterol are available only with your doctor's prescription. Other strengths of ergocalciferol are available without a prescription. However, it may be a good idea to check with your health care professional before taking vitamin D on your own. Taking large amounts over long periods may cause serious unwanted effects.

Importance of Diet

For good health, it is important that you eat a balanced and varied diet. Follow carefully any diet program your health care professional may recommend. For your specific dietary vitamin and/or mineral needs, ask your health care professional for a list of appropriate foods. If you think that you are not getting enough vitamins and/or minerals in your diet, you may choose to take a dietary supplement.

Vitamin D is found naturally only in fish and fish-liver oils. However, it is also found in milk (vitamin D–fortified). Cooking does not affect the vitamin D in foods. Vitamin D is sometimes called the "sunshine vitamin" since it is made in your skin when you are exposed to sunlight. If you eat a balanced diet and get outside in the sunshine at least 1.5 to 2 hours a week, you should be getting all the vitamin D you need.

Vitamins alone will not take the place of a good diet and will not provide energy. Your body also needs other substances found in food such as protein, minerals, carbohydrates, and fat. Vitamins themselves often cannot work without the presence of other foods. For example, fat is needed so that vitamin D can be absorbed into the body.

The daily amount of vitamin D needed is defined in several different ways.

For U.S.—

  • Recommended Dietary Allowances (RDAs) are the amount of vitamins and minerals needed to provide for adequate nutrition in most healthy persons. RDAs for a given nutrient may vary depending on a person's age, sex, and physical condition (e.g., pregnancy).
  • Daily Values (DVs) are used on food and dietary supplement labels to indicate the percent of the recommended daily amount of each nutrient that a serving provides. DV replaces the previous designation of United States Recommended Daily Allowances (USRDAs).

For Canada—

  • Recommended Nutrient Intakes (RNIs) are used to determine the amounts of vitamins, minerals, and protein needed to provide adequate nutrition and lessen the risk of chronic disease.

In the past, the RDA and RNI for vitamin D have been expressed in Units (U). This term has been replaced by micrograms (mcg) of vitamin D.

Normal daily recommended intakes in mcg and Units are generally defined as follows:

Information about this vitamin-d-and-related-compounds-oral-route-parenteral-route
Persons U.S. Canada
mcg Units mcg Units
Infants and children birth to
3 years of age
7.5-10 300-400 5–10 200–400
Children 4 to 6 years of age 10 400 5 200
Children 7 to 10 years of age 10 400 2.5–5 100–200
Adolescents and adults 5–10 200–400 2.5–5 100–200
Pregnant and breast-feeding
10 400 5–7.5 200–300


  • The total amount of each vitamin that you get every day includes what you get from the foods that you eat and what you may take as a supplement.
  • Your total amount should not be greater than the RDA or RNI, unless ordered by your doctor. Taking too much vitamin D over a period of time may cause harmful effects

This product is available in the following dosage forms:

  • Capsule, Liquid Filled
  • Solution
  • Tablet
  • Capsule
  • Liquid
  • Oil
  • Wafer
  • Tablet, Chewable
  • Suspension
  • Tablet, Disintegrating
  • Capsule, Extended Release