When I began to study marihuana in 1967, I had no doubt that it was a very harmful drug that was unfortunately being used by more and more foolish young people who would not listen to or could not understand the warnings about its dangers. My purpose was to define scientifically the nature and degree of those dangers. In the next three years, as I reviewed the scientific, medical, and lay literature, my views began to change. I came to understand that I, like so many other people in this country, had been brainwashed. Me beliefs about the dangers of marihuana had little empirical foundation. By the time I completed the research that formed the basis for a book, I had become convince that cannabis was considerably less harmful than tobacco and alcohol, the most commonly used legal drugs. The book was published in 1971; its title, Marihuana Reconsidered, reflected my change in view.

At that time I naively believed that once people understood that marihuana was much less harmful than drugs that were already legal, they would come to favor legalization. In 1971 I confidently predicted that cannabis would be legalized for adults within the decade. I had not yet learned that there is something very special about illicit drugs. If they don't always make the drug user behave irrationally, they certainly cause many non-users to behave that way. Instead of making marihuana legally available to adults, we have continued to criminalize many millions of Americans. About 300,000 mostly young people are arrested on marihuana charges each year, and the political climate has now deteriorated so severely that it has become difficult to discuss marihuana openly and freely. It could almost be said that there is a climate of psychopharmacological McCarthyism.

One indication of this climate is the rise in mandatory drug testing, which is analogous to the loyalty oaths of the McCarthy era. Hardly anyone believed that forced loyalty oaths would enhance national security, but people who refused to take such oaths risked loss of their jobs and reputations. Today we are witnessing the imposition of a chemical loyalty oath. Mandatory, often random testing of urine samples for the presence of illicit drugs is increasingly demanded as a condition of employment. People who test positive may be fired or, if they wish to keep their jobs, may be involuntarily assigned to drug counseling or "employee assistance" programs.

All this is of little use in preventing or treating drug abuse. In the case of cannabis, urine testing can easily be defeated by chemical alteration of the urine or substitution of someone else's urine. Even if the urine sample has not been altered, the available tests are far from perfect. The cheaper ones are seriously inaccurate, and even the more expensive and accurate ones are fallible because of laboratory error and passive exposure to marihuana smoke. But even an infallible test would be of little use in preventing or treating drug abuse. Marihuana metabolites (breakdown products) remain in the urine for days after a single exposure and for weeks after a long-term user stops. Their presence bears no established relationship to drug effects on the brain. It tells little about when the drug was used, how much was used, or what effects it had or has. Like loyalty oaths imposed on government employees, urine testing for marihuana is useless for its ostensible purpose. It is little more than shotgun harassment designed to impose outward conformity.

Another aspect of psychopharmacological McCarthyism is suggested by the response to a publication in the May 1990 issue of American Psychologist. Two psychologists at the University of California, Berkeley, reported the results of a rigorous longitudinal study of 101 eighteen-year-olds whom they had been following since the age of five to examine the relation between psychological characteristics and drug use. The results showed that adolescents who had engaged in some drug experimentation (mainly with marihuana) were the best adjusted. The authors comment:

Adolescents who used drugs frequently were maladjusted, showing a distinct personality syndrome marked by interpersonal alienation, poor impulse control, and manifest emotional distress. Adolescents who had never experiment with any drug were relatively anxious, emotionally constricted, and lacking in social skills. Psychological differences between frequent drug users, experimenters, and abstainers could be traced to the earliest years of childhood and related to the quality of their parenting. The findings indicate that (a) problem drug use is a symptom, not a cause, of personal and social maladjustment, and (b) the meaning of drug use can be understood only in the context of an individual's personality structure and developmental history. (J. Shedler and J. Block, "Adolescent Drug Use and Psychological Health: A Longitudinal Inquiry," American Psychologist 45 (May 1990): 612-630).

This study suggests that the current anti-drug campaign ("Just Say No") is misguided because it concentrates on symptoms rather than underlying problems.

A hue and cry began immediately. The director of a San Francisco drug prevention program said that it was irresponsible for researchers to report that "dabbling with drugs was 'not necessarily catastrophic' for some youths and may simply be a part of normal adolescent experimentation." A physician who directs the adolescent recovery center of a metropolitan hospital asked, "What does this do to the kids who made a commitment to be abstinent? Now they're being told they're a bunch of dorks and geeks. You can imagine how much more peer pressure is going to be put on them." An author writing in Pride Quarterly (Summer 1990) stated: "Based on the experiences of only 101 subjects, all living in San Francisco, the study still drew national attention due to its outrageous conclusion." Unfortunately," continued the writer, "the permissive thinking which surfaced in the California study will continue to exist in the United States until truly effective drug education reaches beyond the elementary classroom. However, too few educators themselves have seen the latest discoveries about the health consequences of drug use." (J. Diaz, "Furor over Report of Teenage Drug Use," San Francisco Chronicle, May 15, 1990; Pride Quarterly (Atlanta), Summer 1990, pp. 1, 8.) It was all reminiscent of Stalinist party-line criticism of science.

In spite of the illegality of marihuana and the prejudices against it, large numbers of Americans continue to use cannabis regularly. Once considered a youthful indulgence or expression of youthful rebellion, marihuana smoking is now a common adult practice. Millions have smoked marihuana for years, and many of them will continue to smoke it for the rest of their lives. They are convinced that they are harming no one else and not harming themselves, if at all, as much as cigarette smokers or alcohol drinkers are.

Most users, in fact, believe that marihuana enhances their lives -- a subject rarely discussed in print. In more than two decades of research, I have read a great deal about the potential harmfulness of cannabis (much of it nonsense) and very little about its value. Although this value has several aspects, medical use is one of the most important and one that has been seriously neglected. I have come to conclude that if any other drug had revealed similar therapeutic promise combined with a similar record of safety, professionals and the public would have shown far more interest in it. The largely undeserved reputation of cannabis as a harmful recreational drug and the resulting legal restrictions have made medical use and research difficult. As a result, the medical community has become ignorant about cannabis and has been both an agent and a victim in the spread of misinformation and frightening myths.

What follows is largely a book of stories, because most of the evidence on marihuana's medical properties is anecdotal. Some day the systematic neglect of the research community will be remedied and the authors of a book on the medical uses of marihuana will be able to review a large clinical literature. James Bakalar and I hope to reverse prejudices, relieve ignorance, and help prepare the way for that research by exploring the known and potential therapeutic uses of this remarkable substance.

Lester Grinspoon, M.D.

Marihuana, the Forbidden Medicine discusses the use of cannabis for a wide variety of medical problems, including cancer chemotherapy, glaucoma, epilepsy, multiple sclerosis, paraplegia, quadriplegia, AIDS, chronic pain, migraine, pruritus, menstrual cramps, labor pain, depression, and other conditions.