A 27-year-old mother of three has died of water intoxication after competing in a Sacramento radio station contest where people attempted to drink as much water as they could without peeing.

Jennifer Strange was found dead in her suburban Rancho Cordova home shortly after participating in the "Hold Your Wee for a Wii" contest, held by KDND 107.9 on Friday.

Strange had told friends she was hoping to win the prize, a Nintendo Wii video game, for her kids.

It's not known how much water she consumed but contestants started out drinking 240 millilitres of water every 15 minutes before graduating to larger amounts.

Severe headache

Friends noted she left the contest in obvious discomfort.

"She said to one of our supervisors that she was on her way home and her head was hurting her real bad," co-worker Laura Rios said in an Associated Press report. "She was crying, and that was the last that anyone had heard from her."

There was no information on whether she won.

Officials at the radio station said they were shocked to hear about the death.

"We are awaiting information that will help explain how this tragic event occurred," said John Geary, vice president and marketing manager for Entercom Sacramento, the station's owner.

Water intoxication occurs when water enters the body more quickly than it can be removed, upsetting the body's delicate balance of electrolytes, which are critical for nerve and muscle function.

With files from the Association Press