LOS ANGELES, US - A MYSTERIOUS substance that Russian Olympic medalist Oksana Grishuk found in her drink during a business meeting in California tested positive for the date rape drug GHB, police said on Tuesday.

The skater, who won Olympic gold for ice-dancing in 1994 and 1998 while performing under the name Pasha Grishuk, discovered what looked to be a partially dissolved pill in her glass of wine on April 12.

'She was attending a business meeting with at least one other man' at the St Regis Monarch Beach Resort in Dana Point, 97 kilometres south of Los Angeles, according to Orange County sheriff spokesman Jim Amormino.

'She started feeling weird and sick and, when she went to drink from her wine glass, she noticed a partially dissolved pill,' Mr Amormino said. 'She poured the rest of the drink out of the glass, took the pill out and called the police.'

Tests performed on that wine glass, and another glass that investigators retrieved from the lounge where Ms Grishuk, 36, had a pre-dinner drink, came back positive for gamma hydroxy butyrate, he said.

GHB can cause loss of consciousness, breathing problems and possible death in cases of overdose.

Police said an investigation was underway, but declined to give further details.

Ms Grishuk and skating partner Evgeny Platov won Olympic gold in ice dancing at the Lillehammer Games in Norway in 1994 and at Nagano, Japan in 1998. The pair were world champions in the sport for four consecutive years from 1994-1997. -- AFP