Seizures and Hyponatremia Related to Ethcathinone and Methylone Poisoning

We report a case of ethcathinone and methylone poisoning with severe clinical toxicity. This is to our knowledge the first case reported in the medical toxicology literature. A 22-year-old woman was brought to the emergency department following several episodes of tonicoclonic seizures, a few hours after ingesting “legal ecstasy”. The patient needed intubation for recurrent seizures, and she was found to have severe hyponatremia (120 mmol/L) that was corrected with hypertonic saline. The patient's mental status improved rapidly, and she was extubated the day following her admission. However, she developed prolonged rhabdomyolysis (CK 34.537 U/L) that required a 6-day hospitalisation. The seizures and the hyponatremia may be explained by the MDMA-like characteristics of methylone that may induce inappropriate secretion of antidiuretic hormone mediated via the serotonin system. The combination of methylone and ethcatinone (both acting like serotonin reuptake inhibitors) might have contributed to neurologic manifestations compatible with serotonin toxicity, although our patient never had autonomic instability. Our patient had a prolonged period of rhabdomyolysis which may also be explained by excessive serotonin activity resulting in an increased motor hyperactivity. The public has to be aware of this growing health problem. Clinicians must report future cases of toxicity related to the use of cathinone synthetic derivatives in order to increase our knowledge of these substances.