By Rabbi Yair Hoffman

 As of this writing there are twenty states in the U.S. that have now legalized “medical marijuana,” and a number of others on the way as well.  The change in legal status has been both fast and furious.  Proponents claim that it has so many beneficial medical effects.  Opponents of the legalization of marijuana claim that the legalization thus far has been anything but truly “medical.”

The question is how does halacha weigh in on this topic?

Few in either the halachic world or l’havdil the medical world would argue that if the chemical components of marijuana  (THC) were used in medicines that followed the normal way in which medicines are approved, then its use might be recommended and thus halachically permitted when warranted medically.  The push toward legalization, however, has come from grassroots support (no pun intended), rather than from the medical world.  As a consequence, it is not like medicine.


Why is most of the medical world not backing it up thus far?  According to an article in Arthritis Care and research by Mary-Ann Fitzcharles, MD, of McGill University in Montreal, and colleagues, at the current state of affairs, there are a number of issues including  acute and chronic risks, a lack of evidence for efficacy, the absence of data on appropriate dosing.

Sharon Levy, an assistant professor of pediatrics at Harvard Medical School and chair of the American Academy of Pediatrics committee on substance abuse, recently told the Washington Post that she is a strong proponent of studying and developing medications from the active ingredients in marijuana. But she does not support the idea of patients or parents making their own oral preparations and guessing at proper dosage without knowing long-term side effects.   “It is a bad idea. When I look at the accumulation of studies about marijuana and children, I am very concerned,” she said. The authors of the study have written that “Simply acceding to patient demands for a treatment on the basis of popular advocacy, without comprehensive knowledge of an agent, does not adhere to the ethical standards of medical practice,”

One major obstacle to the acceptance of medical use is the wide variation of active compounds in the plant, with THC concentration ranging from 1% to 30% of the plant and blood levels among individuals who inhale it that range from an estimated 7 ng/mL to 100 ng/mL.

It is also interesting to note that of all the tens of thousands of recommendations for medical marijuana in the state of Colorado, almost half of these recommendations had been made by only 15 physicians. This is a clear indication that the medical world has not embraced medical marijuana as the panacea in which the media has marketed it.  The authors of the study point out that the motives for this medical behavior should be questioned and raises ethical concerns.


Back when it was illegal in all fifty states, Rav Moshe Feinstein zt”l addressed the question in his Igros Moshe Yoreh Deah Vol. III #35.  Rav Moshe pointed to no less than nine very serious issues in which  marijuana affects a person.  1] It affects a person physically and 2] mentally.  It further 3] prevents him from studying Torah properly and from 4] davening properly.  It further 5] affects the proper performance of Mitzvos, eliciting a zombie-like element in their performance.   Rav Moshe also presents the idea that 6] elicits within the user a stronger desire for things, and explains that this is one of the problems associated with a Ben Sorer U Moreh, the rebellious son discussed in Dvarim 21:18.  Rav Moshe further explains that it is an 7] abnegation of the Mitzvah of Kivud Av v’Aim, as well as 8] a violation of the Ramban’s understanding of Kedosim ti’hiyu, the commandment to be holy. 9] Finally, Rav Moshe writes that such activity induces the user to violate other Mitzvos in the Torah, thus increasing impurity in Israel.


In consonance with many experts on medical marijuana, two Poskim have voiced to this author their opinion that Marijuana still most certainly constitutes a “gateway drug” leading the user to begin experimenting with other drugs that are illegal and dangerous.  The researchers have said that even in areas where medical marijuana is legal, most users obtain marijuana illegally.  This obligation appears to be a biblical one predicated upon the verse, “venishmartem me’od bnafshosaichem — And you shall be very careful regarding yourselves (Dvarim 4:9).”  not just limited to “veNishmartem” (Dvarim 4:9).  The verse later on (Dvarim 4:15), “Rak hishamer lecha” is understood by most Poskim to actually comprise a second Mitzvah (See Rav Chaim Kanievsky Shlita Shaar HaTeshuvos #25).   There is also a third Mitzvah, “V’Chai Bahem – And you shall live by them” (VaYikra 18:5).


We will start with the physical and mental effects.  According to a long term study of Swedish youth cited by the study, the odds on getting lung cancer if one regularly uses marijuana increase 200%.  Yet another concern is for driving. The authors of the study have noted that impairments can last up to a full day after a single ingestion.

What about the mental effects?  The study cites the possible effects on mood, and particularly depression, and the possibility of dependence. Marijuana use has been linked to higher rates of mental illness, including thought disorders, depression and anxiety, as well as – according to one prominent study published last year – diminished IQ over time.

As far as the other effects mentioned by Rav Moshe are concerned, someone has pointed out that they apply even more so nowadays, because the concentration of THC has clearly increased.  Thus the issues of Bitul Torah, effect upon Davening and Mitzvah performance clearly apply even more.  The same is true with Rav Moshe’s latter points.

In short, the rise of the legalization of medical marijuana is fraught with danger in its current form.  It is sad, because for epilepsy and for other uses, had it been approached through the medical world, it could have been useful and halachically permitted.  At this point, it remains a huge stumbling block and would constitute a biblical prohibition.


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