This is an archived article that was published on sltrib.com in 2016, and information in the article may be outdated. It is provided only for personal research purposes and may not be reprinted.

The federal Drug Enforcement Administration has just issued a helpful reminder to all Americans. In denying a petition to loosen restrictions on marijuana, the agency repeated that the drug has "no currently accepted medical use" in the U.S.

This may come as a surprise, given that 25 states already allow doctors to prescribe marijuana to treat maladies from PTSD to Alzheimer's disease. Yet the truth is, research has yet to find firm evidence that marijuana can alleviate physical suffering.

That the political push for medicinal marijuana has gotten so far ahead of science explains why marijuana is still properly classified as a Schedule I controlled substance. It's also why the Obama administration, in other big marijuana news this week, was right to enable more medical studies of the drug by increasing the supply available to researchers.

Marijuana's unearned reputation as a therapeutic drug is partly an outgrowth of its contradictory legal status in the U.S. Federal law forbids the possession, use and sale of marijuana for any reason. States wanting to get around this prohibition have found it most publicly acceptable to allow limited use, and have latched on to claims that pot can help treat various ailments — for example, the nausea caused by chemotherapy; pain and muscle spasms from multiple sclerosis; epilepsy; Crohn's disease; and glaucoma.

Still, the science behind such claims is, at best, preliminary. And too little is known about marijuana's potential side effects on bronchial and cardiac health, fetal and teenage brain development and, of course, addiction.

Doctors in states that have legalized medicinal marijuana have essentially been left on their own to figure out how to respond to patient requests. Just this week, the Federation of State Medical Boards issued guidelines, which, in the absence of data on marijuana's usefulness, are by necessity limited. Doctors are advised to keep accurate records, to avoid prescribing marijuana to people with substance abuse disorders, to "discuss the risks and benefits," and to remind patients not to operate heavy machinery while under the influence. That's sound advice, but applicable to just about . . . anything.

Marijuana research studies are properly controlled and monitored by both the DEA and the Food and Drug Administration. But they have also been limited more than necessary by a DEA rule that has authorized only the University of Mississippi to grow marijuana for research purposes. Other universities will now be licensed to grow marijuana, and that is expected to greatly expand the supply available for research.

Marijuana is already widely used as medicine in the U.S. The more studies that can get underway, the sooner a confused public can learn with some empirical certainty whether its spread is for good or ill, and the sooner the science can catch up to the politics.