ABSTRACT
Vitamin D is necessary for the regulation of body calcium balance and normal bone development. Overdose is usually given by parents or physicians for the delay in bone and teeth growth. In the excess of vitamin D, complications, such as cardiac arrhythmia and nephrocalcinosis due to hypercalcemia, cause serious morbidity and mortality. In this article, 23 and 14 months old two girls, with high serum calcium and vitamin D levels who were given high dose of vitamin D by physicians and their families are reported. These cases were treated with different protocols without any complication. As a result, physicians should be aware of the danger of that inappropriate use of vitamin D may cause intoxication unless rachitis is proven by laboratory tests, high dose vitamin D should be used.