Hypervitaminosis D

DiseaseDisorder infobox
Name = Hypervitaminosis D


Caption = Cholecalciferol (shown above) and ergocalciferol are the two major forms of Vitamin D.
ICD10 = ICD10|E|67|3|e|65
ICD9 = ICD9|278.4
ICDO =
OMIM =
DiseasesDB = 13939
MedlinePlus =
eMedicineSubj =
eMedicineTopic =

Hypervitaminosis D is a state of Vitamin D toxicity.

The recommended daily allowance is 400 IU per day. Overdose has been observed at 1925 µg/d (77,000 IU per day). Acute overdose requires between 15,000 µg/d (600,000 IU per day) and 42,000 µg/d (1,680,000 IU per day) over a period of several days to months, with a safe intake level being 250 µg/d (10000 IU per day).cite journal |author=Hathcock JN, Shao A, Vieth R, Heaney R |title=Risk assessment for vitamin D |journal=Am. J. Clin. Nutr. |volume=85 |issue=1 |pages=6–18 |year=2007 |month=January |pmid=17209171 |doi= |url=http://www.ajcn.org/cgi/pmidlookup?view=long&pmid=17209171] Foods contain low levels, and have not been known to cause overdose. Overdose has occurred due to industrial accidents, for example when incorrectly formulated pills were sold or missing industrial concentrate cans misused as cans of milk.

Symptoms and presentation

Symptoms of vitamin D poisoning include:

* Dehydration
* Vomiting
* Decreased appetite (anorexia)
* Irritability
* Constipation
* Fatigue

An excess of vitamin D causes abnormally high blood concentrations of calcium (hypercalcemia), which can cause overcalcification of the bones, soft tissues, and kidneys. It can also damage the kidney and produce kidney stones. Ongoing research indicates antagonism with oil soluble menatetrenone, MK-4, an internally transported natural form of vitamin K₂, which is associated with bone formation and calcium retention in the bones.

Note: Hypervitaminosis D symptoms appear several months after excessive doses of vitamin D are administered. In almost every case, a low calcium diet combined with corticosteroid drugs will allow for a full recovery within a month.

Comparative safety statistics

Deaths by vitamin poisoning appear to be quite rare in the US, typically none in a given year. However before 1998, several deaths per year were typically associated with pharmaceutical iron-containing supplements, especially brightly-colored, sugar-coated, high-potency iron supplements, and most deaths were children.cite journal |author=Tenenbein M |title=Unit-dose packaging of iron supplements and reduction of iron poisoning in young children |journal=Arch Pediatr Adolesc Med |volume=159 |issue=6 |pages=557–60 |year=2005 |month=June |pmid=15939855 |doi=10.1001/archpedi.159.6.557 |url=http://archpedi.ama-assn.org/cgi/pmidlookup?view=long&pmid=15939855] Unit packaging restrictions on supplements with more than 30 mg iron have since reduced deaths to 0 or 1 per year.cite journal |author=Tenenbein M |title=Unit-dose packaging of iron supplements and reduction of iron poisoning in young children |journal=Arch Pediatr Adolesc Med |volume=159 |issue=6 |pages=557–60 |year=2005 |month=June |pmid=15939855 |doi=10.1001/archpedi.159.6.557 |url=http://archpedi.ama-assn.org/cgi/pmidlookup?view=long&pmid=15939855]

These statistics compare with 59 deaths due to aspirin poisoning in 2003, [http://www.aapcc.org/Annual%20Reports/03report/Annual%20Report%202003.pdf 2003] at American Association of Poison Control Centers] 147 deaths associated with acetaminophen-containing products in 2003, and an average of 54 deaths per year due to lightning. [ [http://www.lightningsafety.com/nlsi_lls/fatalities_us.html 1990-2003] ]

Special Cases

Vitamin D toxicity is unlikely except when certain medical conditions are present, such as primary hyperparathyroidism, sarcoidosis, tuberculosis, and lymphoma. Vitamin D deficiency is much more likely in most parts of the world. [ [http://lpi.oregonstate.edu/infocenter/vitamins/vitaminD/ Vitamin D] . The Linus Pauling Institute] cite journal |author=Vieth R |title=Vitamin D supplementation, 25-hydroxyvitamin D concentrations, and safety |journal=Am. J. Clin. Nutr. |volume=69 |issue=5 |pages=842–56 |year=1999 |month=May |pmid=10232622 |doi= |url=http://www.ajcn.org/cgi/pmidlookup?view=long&pmid=10232622]

References

See also

* Vitamin poisoning

External links

* [http://www.drugs.com/enc/hypervitaminosis_d.html Hypervitaminosis D Medical Information]