Rhabdomyolysis and the Use of Low-Dose Amphetamine

Abstract

Rhabdomyolysis ranges from being asymptomatic with elevated creatine kinase (CK) to a potentially lifethreatening condition involving multiple organ systems. Muscular trauma is the most common cause, followed by enzyme deficiencies, electrolyte abnormalities, drugs, toxins, and endocrinopathies. While these risk factors are delineated, it is not clear if mild exposure to a combination of risk factors could lead to the development of rhabdomyolysis. In this case report, a 22-year-old male of Pakistani/Caucasian ethnicity presented to the emergency room with myalgias and tea-colored urine after starting a new exercise program. His serum CK level and liver function tests were significantly elevated. He was successfully treated for acute rhabdomyolysis with aggressive hydration. However, the etiology of his condition was not clear given that his exercise was not considered vigorous. The only plausible explanation for his symptoms included the use of prescribed dextroamphetamine, which may have exacerbated the physiologic responses induced by exercise. This report describes a novel case in which a patient may have developed recurrent episodes of rhabdomyolysis due to low-dose dextroamphetamine use. The combination of exercise and dextroamphetamine use may predispose patients to develop rhabdomyolysis.

Methylphenidate-Associated Creatine Kinase Level Elevation

“…Previous cases of methylphenidate use-associated CK elevation were reported in conjunction with serious adverse reactions (eg, rhabdomyolysis, 4 NMS, 5,6 hyperthermina, 7 segment (ST)-elevation myocardial infraction, 8,9 and myopathy 10 ), but all were because of injection or immediate-release tablets rather than the same PR formulation used here (Table 1). In addition, amphetamines similar to those used clinically for ADHD in adults and their synthetics are reported in, agitation, 11 seizure, 11–15 and CK elevations concurrent with hyperpyrexia, 12,15,16 rhabdomyolysis, 12,13,16–28 myoglobinuria, 28,29 and serotonin syndrome, 27 progressing to renal impairment, 17,19,21,22,24,30,31 arrhythmias, 15,22 cardiorespiratory arrest, 13 disseminated intravascular coagulation, 16,19 impaired liver function, 18,19 and death. 13,16,21,22,26 Lisdexamfetamine, recently approved in Japan for ADHD treatment has already increased the CK levels in cases of poisoning in cats.…”