Vitamin D Toxicity due to a Commonly Available “Over the Counter” Remedy from the Dominican Republic

Abstract

CONTEXT: Hypercalcemia in ambulatory patients is occasionally caused by vitamin D toxicity. OBJECTIVE: We report nine patients presenting to Columbia University Medical Center with hypercalcemia due to a supplement from the Dominican Republic containing massive amounts of vitamin D. METHODS: Case histories and laboratory evaluation (calcium, PTH, vitamin D metabolites) are discussed in the context of other published cases of vitamin D toxicity. The supplement was analyzed by HPLC to quantitate vitamin D and A content. RESULTS: Nine patients presented with hypercalcemia (range, 10.8-17.2 mg/dl; normal, 8.4-9.8 mg/dl), suppressed PTH (range, <3 to 11 pg/ml), and elevated 25-hydroxyvitamin D (range, 94-525 ng/ml; normal, 30-80 ng/ml) levels. All reported recently taking an over-the-counter vitamin supplement called Soladek readily available in the Dominican Republic and in Upper Manhattan. Although serum calcium values before the ingestion of Soladek were not elevated (baseline serum calcium range, 8.7-9.2 mg/dl), most had a disorder that can be associated with hypercalcemia [squamous cell cancer (n = 1), Pneumocystis or mycobacterial infection (n = 3), lymphoma (n = 1), granulomatous disease (n = 1), hyperthyroidism (n = 2)]. According to the manufacturer's label, each 5-ml vial of Soladek contains vitamin D (600,000 IU), vitamin A (120,000 IU), and vitamin E (5 mg). Laboratory analysis by HPLC revealed that the supplement actually contained vitamin D(3) (864,000 IU) and vitamin A (predominantly retinyl palmitate 123,500 IU) per vial. CONCLUSION: Although hypercalcemia due to exogenous use of vitamin D is unusual, it is important to consider it in the differential diagnosis, particularly among individuals with access to Soladek.