Vitamin D Intoxication in an Adolescent due to Over-Supplementation: A Case Report and Review of Literature.

Background/Objective: We describe a 17-year-old male who presented with symptomatic hypercalcemia due to prolonged, excessive ingestion of vitamin D through homemade milkshakes supplemented with vitamin D3. Case Presentation: The patient presented with abdominal pain, knee pain, and anorexia in the setting of hypercalcemia (15.5 mg/dL [8.4-10.2 mg/dL]). History revealed an intake of homemade milk shake supplemented with vitamin D (vitamin D3 14 045 units/16 ounces): 16 ounces daily for about a year and 32 ounces daily for 10 days prior to his presentation. Further workup revealed: corrected calcium 13.2 mg/dL, phosphorus 2.9 mg/dL (2.5-4.5 mg/dL), 25-hydroxyvitamin D 594 ng/mL (30-100 ng/mL), 1,25 dihydroxyvitamin D 101 pg/mL (19-83 pg/mL), and parathyroid hormone 6.9 pg/mL (7.5-53.5 pg/mL), confirming a diagnosis of hypervitaminosis D. The patient was treated with intravenous fluids and a low calcium diet with improvement in symptoms in 2 days and resolution of hypercalcemia within 1 month and vitamin D level in 6 months. Discussion: There have been few reports of vitamin D intoxication in adolescents. Our patient knowingly consumed vitamin D, but neither he nor his family knew the exact quantity he was taking or the risks of excess intake, a scenario consistent with other adolescent cases of vitamin D toxicity. Conclusion: Health care providers should be aware of the dangerous practice of vitamin/supplement abuse by young individuals and should inquire about supplement use and educate them about the detrimental effects associated with inappropriate intake of certain supplements, such as vitamin D.