Fat burn X: burning more than fat.

A 50-year-old man presented with a 2-day history of bilateral lower extremity cramping and dark urine. The patient was found to have a creatine phosphokinase (CPK) elevated of up to 2306 U/L, a serum uric acid of 9.7 mg/dL and 101 red blood cell's per high-powered field on urinalysis. On questioning, the patient endorsed daily exercise with free weights. There were no changes in his regular exercise and medication regimen, no muscle trauma, no recent drug use and no illness. The patient did mention using a new fat burner known as 'Fat Burn X', which he had begun taking 2 days prior to the onset of his muscle cramps. The patient was given normal saline intravenous fluid resuscitation for 48 h with resultant normalisation of his CPK and creatinine, and was discharged with primary care follow-up. 2016 BMJ Publishing Group Ltd.