Background: Vitamin D intoxication, though rare, can be severe. We present a patient with severe vitamin D intoxication after consuming highly concentrated supplements bought online.
Case presentation: A previously healthy man presented with nausea, frequent urination and fatigue. He was admitted with hypercalcemia and acute renal failure: creatinine at 311 μmol/l, eGFR 19 ml/min/1.73 m2, albumin-corrected calcium 3.02 mmol/l, and Vitamin D levels above the upper reference limit. He had been using various over-the-counter vitamin D supplements bought online for six months. Treatment with intravenous fluids was successful. Kidney biopsy showed nephrocalcinosis, and renal function normalised within a year, though vitamin D levels remained elevated for six months.
Interpretation: The recommended daily vitamin D intake is 10 mcg (adults > 70 years: 20 mcg). Highly concentrated over-the-counter vitamin supplements are readily available, and careless use can be dangerous. We recently treated three patients who were admitted with hypercalcemia and severe acute kidney failure after using the same over-the counter liquid vitamin D supplement.