The desire for the magic mind drugs is old. Sigmund Freud is one of those who became too excited too early over the wonders of a new brain drug. The result was tragedy.

Freud, one of the early advocates of using drugs to change behavior, took cocaine and found it to be "a magical drug." He pushed it on colleagues. He gave it to his patients. He got his family to use it. He asserted fiercely that the drug had a great many uses -- a treatment for indigestion, for vomiting, for depression, for withdrawal symptoms. It was a stimulant, an anesthetic and more.

Freud's eager proselytizing led eventually to the death of a close friend and a patient. Freud finally stopped using cocaine, but not before he gained a reputation as the man who brought to Europe "the third scourge of humanity." Alcohol and morphine were the others.

A few decades later, the mind drug amphetamine swept into fashion and eventually sold some 12 billion pills in one year. One enthusiastic doctor, in 1946, listed no less than 39 medical uses for amphetamines -- to treat epilepsy, Parkinson's disease, schizophrenia, depression, alcoholism, cerebral palsy, colic and even radiation sickness.

Now amphetamines are discredited as treatment for anything except two minor medical problems. But the intervening years caused many thousands of cases of amphetamine "addiction," and the desperate paranoid and hallucinatory withdrawal symptoms that sometimes resulted in suicide.

As several psychiatrists said in an article in Science magazine, patients and some doctors believe, and are encouraged by bold drug advertising to believe, that drugs are "magic bullets" designed to cure their problem.

"The desired effects of a mind drug are conventionally labeled as the main effects, and all other changes are labeled as 'side effects,' regardless of whether they may be positive, negative, uncomfortable, dangerous or massive," the article said.

But it is clear that some mind-altering drugs have had their uses, not because they were "magic bullets" but because they were the most effective (sometimes the only) ammunition available.

In the early 1950s, doctors noticed that chlorpromazine, a drug used by surgeons to dry up secretions during operations, seemed to exert a calming effect as well. As there were no useful psychiatric drugs at the time, almost any chemical was a candidate to be tried on the insane.

The side effects of chlorpromazine can make some patients look stiff and zombie-like, and produce tremors as well after long use, but the drug did have remarkably direct effects on the symptoms of schizophrenia. It simply shut off hallucinations and delusional thinking to a remarkable degree, something psychiatrists still find a little startling.

Similar accidents led to effective and specific drugs to treat severe depression and mania as well. Altogether, the effect of these three new drugs has been stunning:

* The number of patients locked up in state mental institutions dropped rapidly from 560,000 in 1956 to about 140,000 now.

* Though the U.S. population is 10 times as large, we now have about as many inmates in mental wards as we did at the end of the 1800s.