Andrew Naylor, 20, of Derby, downed more than 26 pints after taking the drug, which can cause the body to overheat, the hearing in Sheffield was told.
Dr John Clark, a pathologist, said he died from brain damage caused by water intoxification. He said Mr Naylor consumed more water than his body could cope with, causing fatal swelling.
Mr Naylor bought the ecstasy tablet at the Leadmill night-club in Sheffield. A friend estimated that he drank as many as 30 half-litres of water. He vomited frequently but insisted he was not seriously ill. An ambulance was called and Mr Naylor suffered a seizure on the way to hospital, where he died without regaining consciousness.
The coroner recorded a verdict that Mr Naylor died from non-dependent drug use. He said: "Ecstasy is a dangerous and unpredictable drug."Reuse content