Uniphyline-Induced Hypophosphatemia: A Rare Etiology of Severe Respiratory Failure

Hypophosphataemia is defined as low level of phosphate in the blood (normal range 0.8 - 1.4 mmol/l), which can be drug-induced such as uniphyline. We present a case of elderly female patient with known chronic obstructive pulmonary disease, admitted with acute respiratory failure and low serum phosphate level, her clinical signs and serum phosphate level did not improve with conventional therapy and intravenous phosphate replacement, until her recently commenced uniphyline was discontinued. This highlights the importance of awareness amongst the clinicians about this rare but potential side effect of uniphyline. We suggest monitoring phosphate levels in patients admitted with acute respiratory failure especially those on extended bronchodilator therapy.