ABSTRACTMultiple Acyl-CoA dehydrogenase deficiency (MADD) is an autosomal recessive disorder that can manifest with hepatic and muscular dysfunction. MADD can be fatal in neonates; however, late-onset MADD has a milder course and often becomes symptomatic during adulthood. A 20-year-old patient presented to the hepatology clinic with elevated liver enzymes and hepatomegaly. Several investigations including a liver biopsy were unremarkable. Subsequently, the patient developed rhabdomyolysis and nonketotic hypoglycemia raising suspicion for mitochondrial disorders. Plasma acylcarnitine levels performed showed elevated C4-C18:2 consistent with MADD. Although the patient denied a complete genetic evaluation, the patient had complete resolution of symptoms after riboflavin and diet modification.