A Drug Enforcement Administration official created a stir last week with a formal recommendation to his agency chief that marijuana be made legal for limited medical uses, but any changes are still years away.

The opinion by administrative law judge Francis L. Young amounted to a ringing endorsement of certain benefits from smoking pot - mainly to help cancer patients tolerate highly toxic chemotherapy.Moreover, he concluded that federal law gives officials no choice but to change the way they classify the ancient weed. To do otherwise, he wrote, would be to act in an "unreasonable, arbitrary and capricious" manner.

That is the legal jargon for the criterion courts use to decide whether administrators are acting within the laws they administer or are imposing their own desires.

At the same time, however, Young's decision took tacit note of political realities that left even those strongly favoring his position doubtful that changes are likely for several years.

Laurence O. McKinney, president of a small company called Cannabis Corp. of America in Cambridge, Mass., and a petitioner in the case, was jubilant with the decision because he believes there will be an eventual financial bonanza for his company.

The key word is eventual.

McKinney said in a telephone interview that he is not optimistic the DEA administrator will accept the law judge's finding and predicted it will take at least two years before he and other petitioners can get federal courts to order the finding implemented.