Rhabdomyolysis, the clinical syndrome caused by the injury to skeletal muscle resulting in the release of muscle cell contents into the systemic circulation, has been described in association with various factors. The causes include crush injury, skeletal muscle overuse, heat, drug, abuse of alcohols and metabolic disorders as well as several types of viral and bacterial infections. We report two cases of rhabdomyolysis, which were complicated by uncommon causes, parainfluenza virus type I infection and hypernatremia.