Chronic cannabis use can lead to regular bouts of non-stop vomiting and an obsession with hot showers, Australian researchers have found.

General practitioner, Dr Hugh Allen of Mount Barker Hospital in South Australia, and team report this rare new syndrome in the November issue of the journal Gut.

Allen said he encountered the first case, dubbed patient Y in the paper, in the late 1990s. The patient came to him after a severe bout of vomiting.

"He would vomit continuously for two or three days," Allen told ABC Science Online. "It was so bad he had to go to hospital and be put on a drip."

Two or three months later it happened again, and then the vomiting episodes became more frequent, occurring every month.

The patient was a heavy user of marijuana at the time, said Allen, having started smoking at the age of 19 with the vomit attacks starting when he was 22.

"In all honesty, he was smoking 20 to 40 cones a day," Allen said.

When the patient was in hospital he started to act strangely, said Allen. The patient would sit in a hot shower, which he said relieved his nausea and vomiting.

"It became an obsession with him. He would have 10 to 15 showers a day."

After 15 months of cyclical vomiting, Allen said the patient concluded that his cannabis use was to blame. So he stopped using it and didn't vomit severely for nine months.

But Allen said the patient started using the drug again, and two months later was vomiting.