Alexander Shulgin, the "godfather of ecstasy" who became famous for discovering and experimenting with a host of psychoactive compounds, has suffered a stroke.

His wife, Ann Shulgin, confirmed today that the 85-year-old was in hospital in San Francisco. "Sasha had a mild stroke over [last] weekend and is still in the hospital, where they are treating him. He will be undergoing speech therapy for a while," she said.

Shulgin, a pharmacologist and psychedelic drug pioneer, has been demonised by anti-drug campaigners but also hailed as a counter-culture hero by many more. His work has covered the synthesis of hundreds of psychoactive compounds and his research was published in the 1990s in two books, TiHkal and PiHKAL, which he wrote with his wife.

Shulgin was born in Berkeley, California, in 1925. From the 1960s onwards he synthesised and then sampled hundreds of variations of phenethylamines, drugs related to mescaline, a psychoactive chemical found in cacti, and tryptamines, substances related to the active compounds in hallucinogenic mushrooms.

Friends of the scientist have now launched an appeal for donations to help with his treatment. "We need funds for a lot of things including attempts at archiving his work, and that is something we have been asking for money for. But right now it's simply donations for Sasha's health that we need," said Ann, adding that she expected him to survive and that he was not paralysed.

She said: "The Medicare system in the US pays 80% of certain things but what is left over is considerable, and we are not wealthy. We need around-the-clock care for him right now, and for the next few months, and that can mount up rather fast."

A documentary, entitled Dirty Pictures, which explores Shulgin's lifetime quest to unlock the human mind through psychedelics, is touring film festivals worldwide at the moment.

The compound most associated with Shulgin, MDMA, or ecstasy, was invented by the German drug firm Merck in 1912, and re-synthesised by Shulgin in 1976 for use in psychotherapy settings. Its potential for recreational use was appreciated and the drug soon escaped the clinical confines to become the one of the world's most popular synthetic psychedelics, fuelling the 1980s acid house dance-drug craze. Its influence is still felt in music, art, and design today.

Ann Shulgin is adamant that her husband's extraordinary drug consumption over many decades did not cause his illness. "Considering the hundreds of thousands of people who have experimented with psychoactive drugs and visionary plants, many of them using them as spiritual tools, there is no medical evidence whatsoever that that would be the case. It's simply not true," she said.