Vitamin D deficiency is highly prevalent and there are an increasing number of reports of vitamin D toxicity, mostly related to the misuse of over-the-counter supplements. We report a case with marked hypervitaminosis D (25(OH)D 196 ng/mL) without clinical or biochemical toxicity and normal serum calcium, phosphorus, and 1,25(OH)2D levels. The decline and normalization of the patient's 25(OH)D and urine calcium after cessation of supplements indicated that these supplements were the likely etiology of her hypervitaminosis D. Over-the-counter medications would benefit from regulation by the Food and Drug Administration to prevent incidental toxicity, as seen in our patient.