SUN-763 Energy Drink Induced Severe Hypophosphatemia

Abstract Disclosure: S. Sridhar: None. A.W. Paracha: None. A. Tall: None. A. Ehsan: None. A. Jamil: None. A. Siddiqui: None. Phosphate is a key component of bone/mineral metabolism, energy and nucleic metabolism as well as cellular signaling pathway. Hypophosphatemia is defined as serum phosphate of <2.5 mg/dL, with severe level <1 mg/dL. Phosphate homeostasis depends on renal excretion, intestinal absorption, intra/extracellular shift and bone deposition. It is maintained through the interplay of PTH, 1,25 dihydroxy vitamin D and fibroblast growth factor 23. Several drugs and compounds are implied in the etiology of hypophosphatemia via various mechanisms. Niacin impairs absorption of phosphate by reducing expression of sodium dependent phosphate co-transporter B in the small intestine.34-year-old male with no past medical history presented to the ER for numbness, spasm of upper extremities and chest pressure. Only prodrome was vertigo and numbness one week prior. Routine labs obtained by his primary care physician did not reveal any abnormalities. Labs in ER were notable for serum creatinine 1.01mg/dL (0.7-1.3), bicarbonate 21mmol/L (22-29), phosphate 0.5mg/dL (2.5-4.5), normal calcium, sodium, and potassium levels. PTH was 47.5 pg/mL (15-65), 25-hydroxy vitamin D 23 ng/mL (30-100). Venous blood gas obtained initially showed a pH of 7.5 and pCO2 of 33, with subsequent VBG normal. Urine creatinine of 14.08 mg/dL, urine phosphate < 0.34 mg/dL, due to which fractional excretion of phosphate could not be determined. Further evaluation showed FGF 23 of 29 pg/mL (<=59) and 1 25-(OH)2 D 66.5 pg/mL (19.9-79.3). The only notable behavioral history was recently started high consumption of an energy drink, called Celsius, on a daily basis. This was noted to contain much higher amount of niacin at 130% of recommended daily value.Patient was appropriately repleted with intravenous phosphate and started on oral potassium phosphate sodium phosphate supplementation, which gradually normalized phosphate level. He was discharged on oral phosphate and vitamin D supplementation, with instructions to avoid this energy drink consumption. On repeat labs post discharge, he continued to maintain stable phosphate level over time. The only causative etiology, after ruling out other possibilities, for the severe hypophosphatemia in this patient was his energy drink consumption.Most energy drinks contain caffeine and other ingredients including niacin. One study showed that niacin is found at ∼115% of recommended daily value in these drinks, which consumers are unaware of. High Niacin intake can elicit hypophosphatemia by inhibiting absorption of phosphorus in the small intestine, by blocking the sodium dependent phosphate co-transporter. If severe, it can also lead to respiratory failure and arrhythmias.This case highlights the importance for clinicians to conduct a thorough review of lifestyle factors that may contribute to hypophosphatemia as well awareness for consumers of the risks associated with energy drinks. Presentation: Sunday, July 13, 2025