Brand Name: Ergocalciferol (Vitamin D2), Cholecalciferol (Vitamin D3), Cholecalciferol (Vitamin D3)
Generic Name: vitamin D
Drug Class: N/A
What is vitamin D-oral, and how does it work (mechanism of action)?
Vitamin D is a necessary vitamin for the growth and development of bones. Vitamin D is commonly known as ergocalciferol (Vitamin D2) and cholecalciferol (Vitamin D3). Vitamin D2 and D3 are broken down to their active form, calcitriol, in the body. Calcitriol works by increasing the absorption of calcium and phosphorus in the body. Calcitriol also prevents the loss of calcium and phosphorus from kidneys so they are absorbed back into the body to maintain sufficient levels.
Vitamin D is used for treating hypoparathyroidism, vitamin D-resistant rickets, and low vitamin D levels. Over-the-counter Vitamin D preparations are commonly used for low Vitamin D levels.
What brands are names available for vitamin D-oral?
Ergocalciferol (Vitamin D2), Cholecalciferol (Vitamin D3), Cholecalciferol (Vitamin D3)
Is vitamin D-oral available as a generic drug?
Yes
Do I need a prescription for vitamin D-oral?
Vitamin D2 and D3 50000 IU are available with a prescription. Vitamin D2 and D3 400 – 5000 IU are available over the counter (OTC).
What are the side effects of vitamin D-oral?
Side effects of Vitamin D include:
- nausea,
- vomiting,
- constipation,
- weight loss,
- weakness, and
- increased calcium levels (hypercalcemia).
What is the dosage for vitamin D-oral?
- Hypoparathyroidism: Take 25000 to 200000 IU vitamin D by mouth once daily with 4 grams of calcium lactate 6 times daily.
- Vitamin D resistant rickets: Take 12000 to 500000 IU Vitamin D by mouth once daily.
- Daily intake of vitamin D: Take 600 IU daily.
Which drugs or supplements interact with vitamin D-oral?
Vitamin D should be used with caution with mineral oil because mineral oil slows down the absorption of Vitamin D and reduces its therapeutic benefits.
Thiazide diuretics like hydrochlorothiazide (Microzide) and chlorthalidone (Thalitone) should be used with caution in people with hypoparathyroid taking Vitamin D, because thiamine diuretics may increase calcium levels.

SLIDESHOW
Foods That Aren't as Healthy as You Think See SlideshowIs vitamin D-oral safe to take if I'm pregnant or breastfeeding?
There are no adequate studies done on Vitamin D to determine safe and effective use in pregnant women.
Vitamin D enters breast milk. Therefore, it is best to be cautious before using it in nursing mothers.
What else should I know about vitamin D-oral?
PREPARATIONS: Vitamin D2 and D3 are available in 400, 800, 1000, 2000, 2400, and 5000 international units (IU) tablets and capsules. Vitamin D2 is available in 50000 IU (1.25 mg) softgels. Vitamin D3 is available in 50000 IU capsules.
How should I keep vitamin D-oral stored?Vitamin D capsules and tablets are stored at room temperature between 15 C - 30 C (59 F - 86 F).
Summary
Vitamin D (Ergocalciferol [Vitamin D2], Cholecalciferol [Vitamin D3]) is required for the maintanence for bones and teeth. It works to increase absorption of calcium and to prevent its loss through the kidneys.
Multimedia: Slideshows, Images & Quizzes
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Vitamin D Deficiency: How Much Vitamin D Is Enough?
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Vitamin D Quiz: Test Your IQ of Dietary Supplements
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Related Disease Conditions
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Vitamins and Calcium Supplements
Vitamins are organic substances that are essential for the proper growth and functioning of the body. Calcium is a mineral essential for healthy bones and is also important for muscle contraction, heart action, and normal blood clotting. Check out the center below for more medical references on vitamins and calcium supplements, including multimedia (slideshows, images, and quizzes), related disease conditions, treatment and diagnosis, medications, and prevention or wellness.
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Vitamin D Deficiency
Vitamin D deficiency has been linked with rickets, cancer, cardiovascular disease, severe asthma in children and cognitive impairment in older adults. Causes include not ingesting enough of the vitamin over time, having limited exposure to sunlight, having dark skin, and obesity. Symptoms include bone pain and muscle weakness. Treatment for vitamin D deficiency involves obtaining more vitamin D through supplements, diet, or exposure to sunlight.
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Rickets
Rickets is caused by a deficiency of vitamin D, calcium, or phosphate. Infants and children who are exclusively breastfed, have dark skin, and infants born to mothers who are vitamin D deficient are most at risk for developing rickets. Symptoms and signs of rickets include bone pain, delayed teeth formation, short stature, skeletal deformities (bowlegs, abnormally shaped skull), and decreased muscle strength. Treatment of rickets depends upon the cause, but the first step usually involves correcting any abnormal levels of calcium, phosphate, or vitamin D with supplements.
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Thyroid Cancer
There are four major types of thyroid cancer: papillary, follicular, medullary, and anaplastic thyroid cancer. Tumors on the thyroid are referred to as thyroid nodules. Symptoms of thyroid cancer include swollen lymph nodes, pain in the throat, difficulty swallowing, hoarseness, and a lump near the Adam's apple. Treatment usually involves chemotherapy, surgery, radioactive iodine, hormone treatment or external radiation and depends upon the type of thyroid cancer, the patient's age, the tumor size, and whether the cancer has metastasized.
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Giant Cell Arteritis (GCA or Temporal Arteritis)
Giant cell arteritis, inflammation of blood vessel walls, affects 10%-15% of polymyalgia rheumatica patients. Symptoms and signs of giant cell arteritis include fatigue, weight loss, low-grade fever, jaw pain when chewing, scalp tenderness, and headaches. High doses of cortisone medications are used to treat giant cell arteritis.
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What Foods Are Highest in Vitamin D?
What are the foods highest in Vitamin D? Learn about the best sources to make sure this vitamin is included in your diet.
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What Is the Best Vitamin Supplement to Take?
Dietary supplements are a general term that includes vitamins, minerals, botanicals, probiotics and other products to supplement the diet. The best vitamin supplement differs from person to person depending on their gender, age and any health conditions they have.
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How Do You Know if You're Getting Enough Vitamin D?
Vitamin D is an important hormone in your body that helps you regulate your calcium and phosphorus balance and bone density. The best way to know if you’re getting enough vitamin D is if you get the recommended amount in your diet.
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How Do I Know If I Am Getting Enough Vitamin D?
Vitamin D is an important nutrient that helps your body function properly. The best way to find out if you are getting enough vitamin D through your lifestyle and diet is to take the 25-hydroxy vitamin D blood test.
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What Are the Benefits of Vitamin D?
Vitamin D is an essential nutrient for our bodies. Learn about eight benefits of vitamin D, how to know if you’re getting enough vitamin D, and what to eat to increase vitamin D in your body.
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