IN 1975, Harvard researchers found that marijuana's active ingredient reduced the terrible nausea and vomiting that some cancer patients get from chemotherapy.
They published their conclusion in the nation's best-known medical journal, the New England Journal of Medicine. And the esearchers involved still have confidence in their work. "very comfortable with our conclusions, " said Dr. Emil Frei, professor of medicine at Harvard. "I think they were correct. "
But more than 20 years later, that study and others have faded from memory, or been discounted, as the debate over using marijuana as medicine has grown ever more shrill. The federal "war on drugs" policy has, by some accounts, turned into a ``war on doctors" in California, with federal drug agents questioning at least one physician who recommended medical marijuana under California's new law.
"This has been such a long and festering national argument," said Dr. William T. Beaver, professor of pharmacology at Georgetown University and chairman of a national panel that met last week on the issue.
Last week's panel, convened by the National Institutes of Health, is likely to recommend that more studies be done on whether marijuana is truly medicinal. Beaver said that's the only way to resolve the bitter conflict. "Certainly if nothing is done, you're going to have the ongoing stalemate you have now," he said.
The stakes have risen since voters in California and Arizona passed laws legalizing medical marijuana -- laws that contradict the federal ban on possessing marijuana for any reason. Doctors and patients are caught in the middle of the conflict, fearing the state laws won't protect them from federal punishment.
Activists say that there's plenty of scientific evidence, such as the 1975 Harvard study, to justify the medical use of marijuana. So why convene a panel of scientists to contemplate doing more studies that would delay resolution of the issue for at least a few more years?
That's because the studies done so far are few and small, according to Beaver and other scientists on the panel. Nor are there many formal studies yet of marijuana's use for newer medical problems, such as the wasting syndrome from AIDS, which some doctors say may be the most pressing need.
Nevertheless, the studies already done point out what potential and pitfalls there may be to using marijuana as medicine. Here's a summary of much of the research done to this point:
Cheotherapy nausea
Some disagree with study showing positive benefits
The 1975 Harvard study found that 80 percent of the patients given capsules of marijuana's active ingredient, called THC for tetrahydrocannabinol, cut their nausea and vomiting at least in half. None of those given a ``dummy" pill, or placebo, felt any relief.
Although the study used THC capsules rather than marijuana cigarettes, the author says there is evidence that smoking may be better. "It is true you can control the blood level with smoking much more accurately than with THC," said Frei, the Harvard researcher who also serves as physician in chief at Dana Farber Cancer Center in Boston.
But for every scientist like Frei who supports marijuana as medicine, there is another equally adamant that the drug's medical value is questionable. Richard Gralla, a member of the NIH panel and director of the Ochsner Cancer Institute in New Orleans, for example, believes there are newer drugs more effective than marijuana at easing nausea caused by cancer chemotherapy. Although some patients prefer pot, he said, "the degree of efficacy seems less than that of other agents."
But the newer anti-nausea drugs may not work for all patients, such as those so sick they cannot swallow anything. ``Maybe marijuana would only add something in a subgroup of patients," Beaver said. If studies found this to be true, he said, "then you would have a potentially useful therapy."
Glaucoma
Long-term smoking raises worries
Glaucoma, the second leading cause of blindness, occurs when inner eye pressure increases to the point that it damages the optic nerve. Several studies in animals and humans have shown that smoked marijuana lowers eye pressure quickly and sharply. One 1976 study at the University of California-Los Angeles found smoked marijuana caused an ``impressive" decrease in eye pressure in 10 of 12 glaucoma patients.
But unlike nausea caused by chemotherapy, glaucoma is a long-term condition. That suggests that treating it with marijuana would require frequent and long-term smoking.
"Somebody with glaucoma might wind up having to take this stuff several times a day for decades," Beaver said.
That raises the question of long-term effects of substantial marijuana smoking. Some studies have shown that smoking marijuana damages lungs.
"It's as bad as a conventional cigarette," said Beaver. "You get all those tars and carbon monoxide and products of burning weeds."
While short-term marijuana smoking might not produce much damage, long-term use could have substantially harmful effects, he said.
Neurological problems
Conflicting reports about reducing spasms
Some patients have reported that smoking marijuana prevents or lessens spasms caused by spinal cord injury, multiple sclerosis or epilepsy. But the reports are scattered and inconsistent.
One 1974 report from a Veterans Administration hospital in Florida found that five of 10 men with spinal cord injuries had a decrease in muscle spasms after smoking marijuana. A 1981 New York study of nine multiple sclerosis patients showed that four showed large improvements in muscle-spasm scores after taking THC capsules. And a 1975 report in the Journal of the American Medical Association found one epileptic patient was able to control his seizures by smoking marijuana.
Marijuana might be useful in these neurological cases because it acts quickly and can be used sporadically as needed, Beaver said.
"The spasms can be very distressing," Beaver said. "But people don't have them all the time. If you have something that can be used on an as-needed basis that might act quickly," he said, ``that might be attractive."
But he added, "There isn't really any solid data there."
AIDS wasting
Smoking may work faster than pills
One of the devastating effects of AIDS is a wasting syndrome where patients grow gaunt and weak from weight loss. A few reports have shown that THC capsules stimulate appetite in such AIDS patients, said Kathleen Mulligan, a researcher at the University of California-San Francisco. But the patients didn't gain enough weight to show a statistically significant effect.
AIDS activists insist that smoking marijuana is far more effective than taking THC pills. Beaver said that's plausible but not proven.
The pills deliver THC to the digestive tract. "Maybe only 5 to 10 percent of the drug you swallow gets into the blood stream," Beaver said. "And it's erratic. One person can get a fair amount and the other doesn't get much at all."
Smoking also delivers a variable amount of THC to the body, but it's more direct and faster-acting. The THC goes through the lungs to the bloodstream and through the heart to the brain.
"It's more like getting an intravenous injection when you smoke it," Beaver said.
But smoking marijuana could also have some side effects particularly serious for AIDS patients, he said. AIDS makes some people vulnerable to a rare kind of pneumonia that can be fatal.
If marijuana smoking damages lungs in the same way as tobacco cigarettes, that could make AIDS patients even more susceptible to the pneumonia.
The future
Ongoing quest for more data
Other questions surround the use of medical marijuana, such as whether some patients might be frightened or uncomfortable with the euphoric effects of the drug. Some studies suggest it can increase heart rate, which could be risky in some patients.
But Beaver said the only way to sort out marijuana benefits and risks would be to do careful studies looking at both.
"We really have no idea how many people in the U.S. are using self-administered marijuana for various medical problems," Beaver said. "It might be that half or a quarter of people get a useful response. . . . But then again, maybe it's only one in 50 patients." "That's why we want to get some well-controlled studies."
The NIH scientific panel's mission was to consider the scientific merits of medical marijuana -- not the political ones.
Objections from law enforcement groups that allowing the medical use of marijuana would encourage recreational abuse weren't considered, Beaver said. He added that he doesn't believe such arguments.
"We use morphine for people with advanced cancer," Beaver said. "That does not encourage people to shoot up morphine for the fun of it."
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