LSD, the drug that launched the psychedelic era and became one of the resounding symbols of the counterculture movement of the '60s, is back in the labs.

Nearly 40 years after widespread fear over recreational abuse of LSD and other hallucinogens forced dozens of scientists to abandon their work, researchers at a handful of major institutions - including UCSF and Harvard University - are reigniting studies. Scientists started looking at less controversial drugs, like ecstasy and magic mushrooms, in the late 1990s, but LSD studies only began about a year ago and are still rare.

The study at UCSF, which is being run by a UC Berkeley graduate student, is looking into the mechanisms of LSD and how it works in the brain. The hope is that such research might support further studies into medical applications of LSD - for chronic headaches, for example - or psychiatric uses.

"Psychedelics are in labs all over the world and there's a lot of promise," said Rick Doblin, director of the Multidisciplinary Association for Psychedelic Studies in Santa Cruz. "The situation with LSD is that because it was the quintessential symbol of the '60s, it was the last to enter the lab."

LSD - lysergic acid diethylamide - is a synthetic psychedelic drug and one of the strongest hallucinogens in the world.

Created in Switzerland in 1938, LSD was used primarily for psychiatric research through the next couple of decades before it burst onto the counterculture scene as a recreational drug.

Harvard University Professor Timothy Leary, along with a handful of scientists, began promoting LSD use for the psychedelic trips. With a fairly small dose, users discovered they could experience vivid visual hallucinations and altered consciousness. But as recreational use increased, so did cases of users having negative and even dangerous experiences with the drug, especially when they mixed LSD with other drugs.

Polarizing issue

Researchers were using LSD to explore treatment into everything from alcoholism and drug addiction to anxiety in cancer patients. But as notoriety of the drug spread, it became a polarizing issue among serious scientists, many of whom abandoned their research.

In 1966, the federal government made LSD illegal, and by the early 1970s, research into all psychedelic drugs in humans had come to a halt, although some scientists continued to study the drugs in animals.

"What poisoned the well was the widespread abuse being promoted by scientists to the public," said Dr. John Mendelson, an associate professor of medicine and psychiatry at UCSF who is helping run the LSD study. "That put a lot of researchers off, and it made it very hard for researchers to justify getting back into the field. And there were no pressing health needs, no pressing treatments other than curiosity."

Researchers at UCLA were among the first to return to hallucinogen studies, starting with the drug ecstasy about 10 years ago. Research into psychedelic drugs expanded, with prominent labs around the country studying ecstasy and natural hallucinogens like psilocybin, or magic mushrooms, and peyote.

But LSD, still in disrepute, remained off-limits. The first studies involving LSD in human subjects started last year at Harvard University, and the UCSF study is only the second in the country. At Harvard, scientists are studying potential uses of LSD to treat cluster headaches - chronic headaches that affect sufferers during months-long cycles several times a year.

The federal government never banned LSD outright for use in research, but for decades it was nearly impossible to get funding or federal approval.

As research into hallucinogens has slowly picked up, private and nonprofit groups have sprung up to seek funding sources.

It still isn't easy to get an LSD study off the ground. Researchers must get permission from the U.S. Food and Drug Administration and the Drug Enforcement Administration plus state regulators, and they need approval from the institution they work for. Then they have to get approval for the source of the actual drug - in the case of UCSF, researchers are using LSD that was manufactured years ago in Switzerland.

Regulatory maze

"Getting through the regulatory maze is quite daunting. It's taken me years to build a system where the FDA and DEA and everyone are happy with how we do our work," Mendelson said. "You have to have a very safe protocol. It's a very cautious system."

Even finding participants for the studies can be a difficult process. The UC researchers usually have to screen 100 volunteers before they can find one who meets their needs. Subjects must have done LSD at least a couple of times before, Mendelson said.

"You don't want people who are looking for a legal way to get a first experience," he said. "This isn't fun. There's no Grateful Dead music playing. This is serious business."

Stanislav Grof was one of the last scientists to abandon hallucinogenic research when he shut down several projects at the Maryland Psychiatric Research Center in 1973 after his funding dried up. He moved to California to work at a research institute in Big Sur, where he turned to studies about how to re-create the effects of those drugs through meditation and breathing techniques.

Mixed feelings

Now semiretired and living in Mill Valley, Grof said he has mixed feelings about the re-emergence of hallucinogen studies. He's pleased to see some of the stigma falling away from drugs like LSD, but it bothers him that the scientific community lost decades of research.

"I thought psychiatry and psychology really lost a major opportunity because of the abuse that happened with unsupervised research," Grof said. "These are fascinating substances - and they're very, very powerful, so they should be used with great precaution."