MARIJUANA IS NOT MEDICINE
SOMEBODY HAD BETTER TELL YOUR DOCTOR!

by Dan Brookoff, M.D., Ph.D.

I give people dangerous drugs.
I am responsible for a lot of people using narcotics.
I am an oncologist.
I do not recommend marijuana.

IS MARIJUANA A MEDICATION?

          My definition of a medication is a drug treatment that is aimed at one of the following three goals:  1) the prolongation or preservation of life,  2) the support of functioning or  3) the relief of discomfort.  The use of drugs for other purposes is not medicine.  My guiding principle in caring for a patient is that any medication that I use must be the best available treatment for that particular situation.  Because of this, marijuana cannot be considered a medication.

IS MARIJUANA NOT A MEDICATION BECAUSE IT IS TOXIC?

          Some of the drugs we use in the medical treatment of cancer have toxic side effects.  The toxic effects of a drug don't necessarily disqualify it as a medication. Sometimes it is worth using a very toxic medication if the potential benefits are great.  For example, many cases of leukemia can be cured but at the cost of severe side effects.  In some cases, the severe side effects are not a risk — they are a certainty.

IS MARIJUANA NOT A MEDICATION BECAUSE IT IS UNCONVENTIONAL?

          Just because a treatment is not "conventional" doesn't disqualify it as a medication, either.  Sometimes, there are no conventional treatments available for a particular problem.  After weighing the risks and benefits of an unusual treatment, my patient may feel that he or she wants to undergo an alternative therapy.  If I am sure that my patient is fully informed, is not forgoing a treatment that has a better potential for success, and is not exposing himself or herself to needless risk, I (and many physicians) will help the patient gain access to that treatment.  I have certainly recommended alternative medical treatments for several of my patients with AIDS and, frankly, I am glad that I did; however, marijuana is neither an acceptable medical treatment nor an alternative medical treatment for any illness.

BUT MARIJUANA CAN RELIEVE CHEMOTHERAPY‑INDUCED NAUSEA; ISN'T THAT AN IMPORTANT PROBLEM?

          When one of my patients has a cancer problem that can be helped by treatment with chemotherapy medications, I will recommend that we proceed with treatment.  Many of these drugs have serious side effects that we must take into consideration and be prepared to manage.  Often, I will also recommend the use of medications to alleviate symptoms caused by the cancer (such as the judicious use of narcotic medications for the relief of pain).  I will also use medications to relieve the symptoms caused by chemotherapy treatments, such as nausea.

          Whenever I recommend that a patient undergo chemotherapy treatment, I always make sure that we have a lot of time to discuss the effects of a particular treatment and how they will be managed.  I find that the word "chemotherapy" usually evokes a lot of anxiety.  People facing the prospect of chemotherapy invariably know of someone who underwent cancer treatment and suffered a great deal of discomfort.  The most frightening symptom that people associate with chemotherapy is not pain, but rather uncontrollable nausea and vomiting.  While this is not a problem with many types of chemotherapy treatments, it has been common enough over the years to give rise to a lot of legitimate fear.  The good news is that within the last 10 years, safe and effective treatments for chemotherapy-induced nausea and vomiting have made this fear a thing of the past.

IS THERE EVER A CIRCUMSTANCE IN WHICH MARIJUANA IS THE BEST AVAILABLE TREATMENT FOR CHEMOTHERAPY-INDUCED NAUSEA AND VOMITING?

          I never recommend that my patients use marijuana.  I want to explain why in the most balanced and compassionate way I can.  To understand why I feel the way I do, it is important to understand some of the medical details about chemotherapy-induced nausea and vomiting.

          Chemotherapy drugs cause nausea by stimulating an area of the brain called the chemoreceptor trigger zone.  Typically, nausea and vomiting begin 90 minutes to three hours after the administration of the chemotherapy and can last for up to six hours.  For certain chemotherapy medications, such as platinum and intravenous cyclophosphamide, the onset of nausea may be delayed for up to 18 hours and may have a somewhat more prolonged course of up to four days.  Patients whose nausea and vomiting have been poorly controlled can become conditioned into developing anticipatory nausea, which can begin even before the treatment begins.  Since there are several different chemical receptors in the brain which control the sensation of nausea, several different types of drugs have proven effective in its treatment.  All of these medications need only be used for very limited periods of time.

          The most successful group of anti-nausea drugs has been the recently introduced medications which block serotonin receptors in the chemoreceptor trigger zone, such as ondansetron.  These medications have proven to be safe and effective for both adults and children and generally have only mild side effects.  Another group of drugs which has proven safe and effective for the treatment of chemotherapy-induced vomiting are medications which block dopamine receptors, such as metoclopramide and haloperidol.  Other dopamine-blocking medications as the phenothiazine medications (which include Thorazine and Compazine) are somewhat effective but are inferior and remain "third choice" medications.  Other medications, such as certain steroids and minor tranquilizers, have proven safe and effective for the treatment of chemotherapy-induced nausea and vomiting, usually when used in conjunction with another anti-nausea drug.

WHAT ABOUT DRUGS DERIVED FROM MARIJUANA?

          A class of drugs derived from marijuana called the cannabinoids has also been shown to have some anti-nausea effects, but this activity is no greater than that of third-choice drugs.  Cannabinoids also cause more side effects than the other anti-nausea drugs (sedation, dizziness, low blood pressure, and an unpleasant sensation called dysphoria).  A purified form of the cannabinoid Delta-9 THC has been available on the American market for eight years under the brand name Marinol.  Despite its availability it has found limited use, because it generally doesn't work.  If you look at the advertisements for Marinol placed in the medical journals by its manufacturer (Roxane Laboratories), it is touted as "more effective than Compazine," which is a third-choice medication for the treatment of chemotherapy-induced nausea and vomiting.

IS MARIJUANA MORE EFFECTIVE THAN THE DERIVATIVES THAT ARE CURRENTLY ON THE MARKET?

          Every few years, the lay press brings up the issue of using inhaled marijuana for the treatment of chemotherapy-induced nausea.  For physicians, this issue was settled 10 years ago when Dr. M. Levitt and colleagues conducted a randomized double-blind comparison of Delta-9 THC and marijuana for the treatment of chemotherapy-induced nausea and vomiting.  (This is published in the 1984 Proceedings of the American Society of Clinical Oncology, volume 3, page 91.)  What they found was that neither agent was particularly useful (75 percent of patients in both groups suffered significant nausea and vomiting), and among patients expressing a preference, Delta-9 THC was chosen the best agent.  Inhaled marijuana has nothing to add to the limited benefits of purified Delta-9 THC.  It does carry added risks due to its method of delivery and its impurity.  This includes toxic effects on the lungs, additional side effects, and the danger of infection from fungus which is often found in marijuana cigarettes.  Marijuana is never the best available treatment for a patient, and that is why it is not a medication.

IF MARIJUANA ISN'T A MEDICATION, WHY AREN'T PHYSICIANS UP IN ARMS ABOUT THE CURRENT MOVEMENT TO LEGALIZE ITS USE FOR CANCER PATIENTS?

          Most physicians are unaware that this is really an issue; for them the issue was settled years ago.  Years ago, when there were no effective medications on the market for the treatment of chemotherapy-induced nausea and vomiting, the American Medical Association considered the therapeutic potentials and hazards of marijuana.  As they examined its emerging therapeutic possibilities, they found more and more evidence that marijuana was hazardous to health.  (Journal of the AMA, Oct. 16, 1981, volume 246, pages 1823-1827.)

          Nonetheless, many physicians (including me) had patients who participated in treatment trials using inhaled marijuana in the late 70s and early 80s because, at the time, there was no better alternative.  With the therapeutic potential of marijuana eclipsed by safer and more effective drugs, we have come to the conclusion that there is no therapeutic use for marijuana.  All we are left with are the hazards.  These include lung disease, cardiac dysfunction, brain damage, genetic damage, immune disorders and psychomotor impairment.

HOW CAN PHYSICIANS' NON-RESPONSE TO THE ISSUE OF THE MEDICINAL USE OF MARIJUANA BE EXPLAINED?

          I have to admit that when I was first confronted with the issue of "medical marijuana" by my friends in the prevention field, I couldn't get very excited about it.  I felt that the facts obviously showed that there was no medicinal use for inhaled marijuana and, as such, it was not a subject worthy of serious concern.  As I mentioned to a friend, I classed the medical use of marijuana right up there with the issue of therapeutic bathing in Drano!  I was against that too, but I couldn't see that anybody could seriously be in favor of it.

HASN'T THERE BEEN RECENT SCIENTIFIC EVIDENCE TO SHOW THAT MARIJUANA CAN BE USEFUL AS A MEDICATION?

          If you look up "marijuana" in the last few years of the journal used by most clinical oncologists (Journal of Clinical Oncology) you'll find only one mention of marijuana (a sign that it's not a hot topic for us).  That mention is made in an article by Richard Doblin and Mark Kleiman, of Harvard University, that reports a survey that they conducted of physicians and that purports to "suggest that support for rescheduling marijuana is indeed present in at least a significant minority of our population (oncologists)."

          The report, which appears in the Journal of Clinical Oncology volume 9, pages 1314-1319, does not mention how the authors selected doctors to respond to their survey, and it also doesn't mention the authors' affiliation with any of the pro-marijuana organizations to which they belong (no bias there?).  While this article did not have much of an impact on oncologists, mention of it was made in letters to many medical journals — letters written by Doblin and Kleiman.  These letters were generally ignored by physicians.  This would almost be funny if all these references weren't being used by pro-marijuana forces to convince ill-informed government officials that there is medical evidence to support the use of marijuana.

WHAT ABOUT THE BOOK ON MARIJUANA WRITTEN BY A PROFESSOR AT HARVARD MEDICAL SCHOOL?

          Another source cited as evidence of the therapeutic effects of marijuana is a book that was recently written by Dr. Lester Grinspoon of the Harvard Medical School ("Marihuana, the Forbidden Medicine").  The book is poorly written, unscientific, and makes some absolutely bizarre claims for the use of marijuana.  (For example, Dr. G. says it promotes safe driving!)  Many people in the prevention field were justifiably angered when they read this book.  I read the book, and I found it very disturbing.  I must say that my predominant emotional reaction was to feel sorry for Dr. Grinspoon.