Mrs Urlayeva, who is a member of the opposition free peasants party, was arrested in the capital, Tashkent, on Saturday and incacerated in the mental health ward of a city hospital.
Talib Yukabuv, chairman of the Human Rights Society of Uzbekistan, said Mrs Urlayeva had been detained in the past and forcibly injected with drugs. "It is because she is such a persistant critic who works 24 hours a day to help the people" he said.
Yesterday the Helsinki federation for Human Rights called for her immediate release.