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Medical Experiments Performed on Humans

Rav Chaim Navon
The Israel Koschitzky Virtual Beit Midrash

Halakha: A Weekly Shiur In Halakhic Topics
Yeshivat Har Etzion




Shiur #11: Medical Experiments Performed on Humans


Rav Chaim Navon



When discussing trials conducted on human beings, we must distinguish between conducting an experiment upon the patient himself, who tries out a treatment that has not yet been fully tested, and conducting an experiment upon a healthy person. Let us begin with the case where the patient himself is offered some experimental treatment.[1] In a situation where the patient is close to death, he merely endangers transitory life (chayyei sha'a). Regarding such a case, the Shulchan Arukh rules, in the wake of the Gemara, that there is room for allowance:


[If a person is afflicted with] a disease or illness that constitutes a danger for which Shabbat may be desecrated, he may not be treated by a heathen unless he is a generally recognized expert, for we are afraid that he will kill him. Even where there is uncertainty whether he will live or die, he may not be treated by him. But if he will certainly die, he may be treated by him, for we are not concerned here about transitory life. (Shulchan Arukh, Yore De'a 155:1)


            In other words, one is forbidden to visit a heathen doctor, for it is very likely that he will kill him. If, in any case, he is dying, he is permitted to risk his transitory life for the possibility that he may be cured. The Maharsha draws an inference from this case regarding uncertain medical practices:


I inferred from here about what I had been asked regarding a patient whose doctor prescribed an emetic for him so that he might vomit. He told him that if the medicine fails, he will die immediately, but if it does work, he will be cured; if, however, he doesn't take the emetic, he will certainly die within a short time. (Gilyon Maharsha, ad loc.)


            The author of Responsa Shevut Ya'akov issued a similar ruling:


[I was asked] by an expert doctor about a certain patient who was ill with a life-threatening illness, and all the doctors assess that he will certainly die within a day or two. They say, however, that there is yet another medicine that might cure him, but the opposite is also possible: if he takes the medicine, and it does not succeed [in curing him], God forbid, he will die immediately within an hour or two. Is he permitted to take this medicine, or are we concerned about transitory life, and so it is better to sit back and do nothing?

Answer If it is possible that on account of this medicine, he will fully recover from his illness, then we certainly do not concern ourselves with transitory life… Thus, in our case as well, since he will certainly die, we abandon what is certain, and seize what is in doubt, perhaps he will be cured. In any case, the doctor must not act hastily, but rather he must be very moderate in the matter, consulting with expert doctors in the city and acting in accordance with the majority opinion, that is, a clear-cut majority which is double, for we must be concerned about those who are lightheaded. Therefore, he must act in accordance with the majority view among the doctors and the consent of the local Torah sage. (Responsa Shevut Ya'akov, III, no. 75)


            Responsa Achi'ezer relates to the likelihood of success of the experimental treatment:


Regarding the question that was proposed regarding a certain patient, whose expert doctors say that without surgery, he will not live for more than six months, and with the surgery, he might live, but the surgery is very dangerous, and it is more likely that he will die more quickly…

The [author of the] book Mishnat Chasidim was in doubt, and he proposed that there must be an even doubt, that the likelihood of him living is equal to the likelihood that he will die immediately. However, the statement that "we are not concerned about transitory life" implies that we do not distinguish, so that in a situation where [the patient] will certainly die without the surgery, we do not concern ourselves with transitory life… Furthermore, regarding what the Mishnat Chakhamim proposed, that each time he needs permission from the court. It is certainly fitting to contemplate this, and to rely on the doctors who are greater experts. According to what you say, that the senior doctors of Koenigsburg unanimously approved, one must rely upon them. (Responsa Achi'ezer, II, Yore De'a 16, letter 6)


            According to R. Chayyim Ozer, one is permitted to offer a terminal patient experimental treatment, even when the chances of success are low, and in all likelihood the treatment will hasten his death, rather than bring him salvation. He also notes that in such a case we follow the majority opinion among the doctors.


            Another issue that the posekim raise in this connection concerns the definition of "chayyei sha'a" – transitory life. Life of what expected duration are we permitted to endanger?


See Hagahot Chokhmat Shelomo who researched this matter, [concluding] that no measure was given regarding chayyei sha'a. And you can't say that if a person will die within a year or two, this too should be considered chayyei sha'a. For if that is the case, what is chayyei olam? Surely everyone is eventually going to die; what is the difference between one year, two years, or [even] a hundred years, a person is not going to live forever, and so everything should be considered chayyei sha'a! It is difficulty to say that only if he will die from the illness [from which he now suffers] is it considered chayyei sha'a, but if he will die from a different illness it is not considered chayyei sha'a. For this is not correct, what is the difference between [dying from] this illness or that one. He writes that from the fact that we maintain that a terefa cannot live twelve months, we see that anyone who, because of a certain illness, cannot live twelve months, and he is expected to die from this illness within the year – his life is considered chayyei sha'a. If, however, he is expected to die only after twelve months, it is not considered chayyei sha'a, but rather chayyei olam. (Darkhei Teshuva, Yore De'a, 155, no. 6)


            According to the Darkhei Teshuva, life expectancy of less than a year is defined as chayyei sha'a for this purpose.


            Responsa Tzitz Eli'ezer discusses the law applying to a person suffering from a mental illness. Under what circumstances are we permitted to consider experimental treatment?


It would appear, in my humble opinion, that there is room to permit an operation of the sort proposed in the question for a dangerously ill mental patient, who must be kept in chains, and his life is in constant danger. Moreover, the lives of others are also in danger. And the expert doctors say that there is no alternative but to perform such an operation. And especially, as it would appear from the wording of the question, that only a minority of such patients die [from the operation], whereas a large proportion of the patients recover, either fully or at least in relation to their condition before the operation. If this is really true, then there is room to be lenient about performing such an operation even for an ordinary dangerously ill mental patient, and not only for one who is very dangerously ill, just as we are lenient about performing an operation for an ordinary dangerously ill patient, even when the operation itself is dangerous. (Responsa Tzitz Eli'ezer, IV, no. 13)


            This is all true regarding a dangerously ill patient, of one type or the other. What, however, is the law applying to a patient who is not dangerously ill? If a person is not afflicted with a life-threatening disease, but he suffers terrible pain, is he permit to try some experimental treatment, which might lead to his death?


            R. Ya'akov Emden writes about this issue as follows:


However, there are those who risk their lives, in order to save themselves from terrible suffering, for example, those who elect to have surgery for gall-stones or kidney stones which cause them great pain and suffering, worse than death. We permit them to do as they like without raising any objections, for sometimes they are saved and healed. Nevertheless, candidates for such surgery should take care. Anyone whose pain does not put him in danger is acting improperly even on a weekday, for a person is not permitted to enter into a situation of uncertain piku'ach nefesh. Even though many have undergone the surgery and were saved, for many the surgery has hastened their death. (Mor u-Ketzi'a, no. 328)


            R. Ya'akov Emden is lenient in that he does not object to those who undergo surgery in order to put an end to their suffering. Were, however, someone to ask him how he ought to act, he would tell him to avoid the surgery, for a person is not permitted to endanger his life in order to relieve himself of pain. There is, however, an authority who is lenient abut this as well:


Regarding the common practice of undergoing surgery even when there is no piku'ach nefesh, it may be suggested that since the person is in pain, he is permitted to [undergo the surgery] in order to free himself of the pain… And furthermore, even if he does not have pain, nevertheless, since the surgery is for the sake of wellness, he is permitted to do this, just as they used to engage in bloodletting. (Shi'urim Metzuyanim be-Halakha)[2]


            The last issue that we must discuss is whether a person is permitted to volunteer for medical experiments. The issue focuses on the question whether or not a person is permitted to endanger himself in order to save others. The Netziv explains that the two Talmuds, the Bavli and the Yerushalmi disagree on this point, and that the posekim have ignored the Yerushalmi, which rules that one must endanger himself. The Netziv writes, however, that as an act of piety one is permitted to do so, but there is certainly no obligation.[3]


            The Radbaz rules on this fundamental issue as follows:


What the Rav of blessed memory writes, "Whoever is capable of saving [another person's] life, and fails to do so, violates the prohibition, 'you shall not stand by your neighbor's blood,' refers to one who can easily save [the other person] without jeopardizing his life in any way, e.g., where the other person is sleeping next to a shaky wall, and he can arouse him from his sleep, but he fails to do so, or where he can testify on his behalf and save him. Such a person violates the prohibition, 'you shall not stand by your neighbor's blood.' What is more, even if there is a small possibility of danger, e.g., where he saw the other person drowning at sea or bandits coming upon him, or a wild beast, all of which are possible dangers, even so he is obligated to save him… Nevertheless, if the uncertainty is close to certainty, he is not obligated to sacrifice himself to save the other person. (Responsa Radbaz, V, no. 218 [1582]).


            According to the Radbaz, a person should not endanger himself in order to save another person, but where there is a only "small possibility of danger," he is required to do so. R. Moshe Feinstein thinks otherwise:


Even though a person is not obligated to put himself into possible danger in order to save another person's life, he is permitted to do so. (Responsa Iggerot Moshe, Yore De'a, II, no. 174)


            In other words, a person is not obligated to endanger himself in order to save another person, but he is permitted to do so, and he does not thereby violate the prohibition against endangering his own life.


            R. Simcha Kook suggests that a distinction be made between medical experiments and the case discussed by the Radbaz, for with respect to medical experiments, "the results of the experiments are distant and indirect." Thus, he is stringent on the matter.[4]


            From all that we have cited above, it stands to reason that a person is permitted to volunteer for research that involves a certain danger. It is wise, however, to carefully examine the benefits vis-a-vis the dangers, and avoid volunteering for dangerous research.




[1] Most of the considerations that we will raise below are not strictly limited to experimental treatments, but to dangerous treatments in general. The danger, however, is the problematic aspect of experimental treatments.


[2] Cited by Prof. A.S. Avraham in Refu'a, Etika, ve-Halakha, II, Jerusalem 1996, p. 636.


[3] Ha'amek She'ela, she'ilta 147, no. 4.


[4] In Refu'a, Etika, ve-Halakha, II, Jerusalem 1996, p. 645.


(Translated by David Strauss)



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