What are the other Names for this Condition? (Also known as/Synonyms)
- Vitamin D Excess
- Vitamin D Intoxication
- Vitamin D Toxicity
What is Hypervitaminosis D? (Definition/Background Information)
- Vitamin D (particularly D2 & D3) is a key nutrient that serve the most important function of maintaining the body levels of calcium and phosphorus
- Vitamin D plays an active role in the formation and preservation of healthy bones, skin, teeth, soft tissues, regulates the body immune system, protects against the sun’s harmful radiation, and is also responsible for reducing the risk of several disorders such as asthma, multiple sclerosis, and rheumatoid arthritis
- If abnormally excess amounts of vitamin D builds-up in the liver, due to a sudden overdose of the substance, or by accumulation of small doses over prolonged periods; it leads to a toxic condition called Hypervitaminosis D
- Hypervitaminosis D disorder causes frequent urination, dizziness, vomiting, and could lead to liver damage
- Discontinuation of vitamin D intake with symptomatic treatment, are the management measures adopted
Who gets Hypervitaminosis D? (Age and Sex Distribution)
- Children (including infants) and adults, who are administered high doses of vitamin D, may be affected by Hypervitaminosis D
- Both male and female sex genders are uniformly affected
- Current research does not indicate any particular racial predominance. But, those in the higher educational and economic strata, are regularly observed to use more vitamin (supplement) pills
What are the Risk Factors for Hypervitaminosis D? (Predisposing Factors)
The risk factors for Hypervitaminosis D include:
- Accidental administration of large doses of vitamin D; especially to infants and children, could lead to acute Hypervitaminosis D
- Individuals who regularly enhance their dietary intake of vitamin D, using vitamin D supplements have a higher risk of the disorder
- Individuals suffering from sarcoidosis, liver dysfunction or kidney dysfunction, suffer more easily from vitamin D over-dosage
- Individuals prescribed certain types of diuretics (water pills) may have a higher risk
It is important to note that having a risk factor does not mean that one will get the condition. A risk factor increases ones chances of getting a condition compared to an individual without the risk factors. Some risk factors are more important than others.
Also, not having a risk factor does not mean that an individual will not get the condition. It is always important to discuss the effect of risk factors with your healthcare provider.
What are the Causes of Hypervitaminosis D? (Etiology)
- The body requires a specific amount of vitamin D each day. The liver stores vitamin D, which then gets transported to various parts of the body by a specific carrier protein, termed as the vitamin D-binding protein. There is a definite limit to the storage ability of the liver, and the vitamin D ‘carrying and dissemination’ capacity of the protein. Consequently, there exists a balance in the body requirement, and between the liver-protein relation
- Any intake of abnormally high levels of vitamin D, causes excessive storage in the liver, upsets the normal balance, and leads to Vitamin D Toxicity. Furthermore, the fat-soluble vitamin D does not get easily excreted out of the body, through urine (unlike other water-soluble vitamins)
- It is important to note that prolonged exposure to sunshine, or regularly consuming vitamin D fortified foods (such as milk products), does not lead to abnormal build-up of body vitamin D levels
What are the Signs and Symptoms of Hypervitaminosis D?
Signs and symptoms of Hypervitaminosis D (which usually manifest over several months of vitamin D high dosage), include the following:
- Excessive thirst, urination, or dehydration
- Vomiting, drowsiness, and nausea
- Eating disorder (anorexia), loss of appetite, constipation
- High blood pressure
- Involuntary muscular contractions (tetany), weak muscles
- Weakness, irritability
- Oral defects in children, which include: Under development of tooth enamel, calcification of the root canal system
How is Hypervitaminosis D Diagnosed?
Diagnostic tests performed for Hypervitaminosis D are:
- Physical presentation and medical history evaluation
- Blood serum analysis for blood calcium, phosphate, vitamin D levels
- Urine analysis including urine calcium level
- Liver function tests
- Testing of bones using x-rays, bone mineral density evaluation
- CT scan of brain
- ECG to test the effect of high calcium levels
Many clinical conditions may have similar signs and symptoms. Your healthcare provider may perform additional tests to rule out other clinical conditions to arrive at a definitive diagnosis.
What are the possible Complications of Hypervitaminosis D?
Complications due to Hypervitaminosis D are:
- Hypercalcemia (buildup of large amounts of calcium): This can cause severe kidney damage and/or kidney failure, kidney stone formation (renal calculus)
- Epileptic seizures; this can be a very serious condition
- Bone and soft tissue over-calcification
- Dental growth problems (in children)
- Premature aging
How is Hypervitaminosis D Treated?
Management of Hypervitaminosis D is achieved by immediately stopping the intake of the vitamin, and treating symptoms accordingly:
- Stoppage of vitamin D, till body attains the required normal level. Until then, a low-calcium diet is prescribed
- Hospitalization may be required if the individual is neurologically impaired, suffers severe dehydration, or shows high levels of calcium on a blood test
- High calcium is treated with bisphosphonates
- Close observation and treatment with intravenous fluids and corticosteroid drugs
How can Hypervitaminosis D be Prevented?
- Vitamin D Toxicity is a disorder that can be completely avoided, or prevented. It is important to assess the required Vitamin D daily allowance, and only the required dose of Vitamin D should be administered accordingly
- It is important to educate individuals (usually adults), who self-medicate or regularly consume vitamin supplements, on the recommended daily dose of these nutrients
What is the Prognosis of Hypervitaminosis D? (Outcomes/Resolutions)
- Discontinuing the intake of vitamin D, and treating the symptoms are generally sufficient enough to ensure a full recovery. The prognosis upon adequate treatment is excellent
- Those with severe signs and symptoms of Hypervitaminosis D may require hospitalization with extended treatment. In some individuals there may be liver, kidney, or nervous system damage; if treatment is delayed. However, mortality is highly infrequent, though in rare instances it is probable
Additional and Relevant Useful Information for Hypervitaminosis D:
- Milk that is fortified with vitamin D is meant to prevent rickets. Rickets is a vitamin D deficiency disorder that causes weak bones and dental deformities
- It is researched that abundant sunshine exposure (such as happening to people of the tropical sunny regions) does not automatically lead to increased levels of vitamin D in the body. There are many other aspects that lead to development of Hypervitaminosis D. These include: genetic factors, skin color and body metabolism capacity
What are some Useful Resources for Additional Information?
Academy of Nutrition and Dietetics
120 S. Riverside Plaza, Suite 2000 Chicago, IL 60606-6995
Phone: (312) 899-0040
Toll-Free: (800) 877-1600
Fax: (312) 899-4873
References and Information Sources used for the Article:
http://www.ncbi.nlm.nih.gov/pubmedhealth/PMH0002561/ (accessed on 2/27/13)
http://www.mayoclinic.com/health/vitamin-d-toxicity/AN02008 (accessed on 2/27/13)
Helpful Peer-Reviewed Medical Articles:
Christensen, W. R., Liebman, C., & Sosman, M. C. (1951). Skeletal and periarticular manifestations of hypervitaminosis D. The American journal of roentgenology and radium therapy, 65(1), 27.
Clark, I., & Smith, M. R. (1964). Effects of hypervitaminosis A and D on skeletal metabolism. Journal of biological chemistry, 239(4), 1266-1271.
Greenbaum, L. A. (2011). Rickets and hypervitaminosis D. Nelson Textbook of Pediatrics. 19th ed. Philadelphia: Sunders, 200-9.
Ham, A. W., & Lewis, M. D. (1934). Hypervitaminosis D rickets: The action of vitamin D. British journal of experimental pathology, 15(4), 228.
Jacobus, C. H., Holick, M. F., Shao, Q., Chen, T. C., Holm, I. A., Kolodny, J. M., ... & Seely, E. W. (1992). Hypervitaminosis D associated with drinking milk.New England Journal of Medicine, 326(18), 1173-1177.