RR21 no. 5758.8


Medical Experimentation: Testing Drugs Made of Pork By-Products



I am a member of the Ethics Committee at the University of Ottawa Heart Institute. At a recent meeting, the committee discussed a protocol for testing a new cardiac drug for which the researchers plan to recruit volunteers from among heart patients. The protocol indicated that a pork by-product was present in the drug. May Jews who observe kashrut participate in this test? I realize that it is permissible to accept pork or pork by-products when these are instrumental in saving one’s life. Yet this is an experiment, and it is uncertain whether this drug will offer any life-saving benefit to these or to future heart patients. Indeed, the researchers inform the volunteers at the time of their recruitment that while the drug may prove useful, it may also turn out to be of no medical consequence at all. (Rabbi Steven H. Garten, Ottawa, Ontario)


A Jew who observes kashrut may participate in the experiment described in our she’elah. We base this conclusion upon two primary arguments. The first has to do with the laws concerning the manner in which one consumes forbidden foods; the second derives from the definition of medicine, which our tradition regards as a mitzvah of the highest order.

1. The Use of Prohibited Substances for Medicinal Purposes.

The Talmud cites the following statement in the name of Rabbi Yochanan: “We are permitted to use anything for healing, with the exception of idolatry, prohibited sexual relations, and murder.”[1] Rashi explains that the word “anything” in this statement refers to isurey hana’ah, substances from which we are prohibited to derive benefit. From here, the halakhic tradition learns that “in a situation of serious illness, we may use for healing any of the substances prohibited in the Torah” outside of those three exceptions.[2] This rule is in accordance with the teaching that the saving of life (pikuach nefesh) is of the highest importance in the Torah and that it takes precedence over virtually all other commandments and prohibitions.[3] From it, we conclude that there is no objection to the use of forbidden foods and their by-products for medicinal purposes, provided that the patient suffers from a serious illness (choleh sheyesh bo sakanah).[4]

The rule in the case of a person whose illness is not a serious one (choleh she’ein bo sakanah) is somewhat more complex. In theory, the prohibition against the forbidden substance still applies. In practice, however, the prohibition can be lifted. The Talmud reports an incident in which Ravina made an ointment for his daughter’s skin out of unripened grapes that were forbidden as orlah.[5] When challenged-“did the Rabbis permit one to do this for a patient whose illness is not a serious one?”-he responded: “have I used these grapes in their normal manner?”[6] This episode serves as a precedent for the codifiers:[7] since as a matter of formal definition the prohibition against eating a forbidden substance applies only to the act technically defined as “eating” or “drinking,” an individual who is not seriously ill may take a forbidden substance for medicinal purposes provided it is administered in an “unusual” manner which differs from the way in which people ordinarily consume it (shelo kederekh akhilatan) or derive benefit from it (shelo kederekh hana’atan). Thus, it is clearly permissible to inject a patient with a drug containing animal blood, because injection is not defined as “eating” and because it does not confer the benefit or enjoyment (hana’ah) normally associated with the ingestion of food.[8] Whether this permit allows a patient not seriously ill to take such drugs orally is the subject of some controversy. Some authorities hold that the patient may swallow the medication, since swallowing is not the normal way of “eating;” others reject this distinction on the grounds that the person at any rate derives some hana’ah from swallowing.[9] Yet here, too, the objection can be met by mixing the forbidden item with “a bitter substance” which removes the possibility of “enjoyment” (hana’ah). Ingesting the forbidden matter in pill or capsule form, or in a liquid mixed with other chemicals, is therefore permitted.[10]

It should also be noted that a forbidden substance might be permitted when it has undergone a physical alteration so extensive that it can be seen as a “new substance.”[11] These considerations play a central role in rabbinic discussions of the kashrut of cheeses and gelatin.[12]

These considerations are brought together in a responsum by the 18th-century R. Ya`akov Reischer on the practice of prescribing a liquid containing dried ram’s blood (bocksblut) as a medication for persons reporting certain symptoms that were not considered life-threatening. Reischer notes that this practice is apparently forbidden, since dried blood is nonetheless “blood” and is explicitly prohibited in the talmudic sources.[13] On the other hand, since the medication was in widespread use among Jews, he decides to apply the dictum “Jewish religious custom has the force of Torah” and to defend the practice. This he does on the grounds that the blood has undergone a substantial physical alteration and that, as an ingredient in the medicinal solution, it is ingested in an “unusual” manner.[14]

In the present case, we must presume that a patient would take the experimental drug in pill or capsule form; hence, the pork byproducts it contains are not consumed in a manner that resembles the halakhic definition of “eating.” These ingredients, moreover, have been subjected to various chemical processes that alter their original form. For these reasons, traditional Jewish law does not prohibit any patient, including one who is not seriously ill, from taking this drug.

2. Medical Experimentation as “Medicine.”

A serious difficulty, however, can be raised against our analysis. While the participants in this experiment are called “heart patients,” it is far from clear that the experimental drug they are to test can be called “medicine.” We do not know that this product is of therapeutic value; indeed, our sho’el reports, it may quite possibly turn out to be of “no medical consequence at all.” If so, then the considerations we have discussed might not apply in our case, since our sources permit the consumption of prohibited substances, albeit in an “unusual” manner, solely for legitimate medical purposes (refu’ah). To permit a Jew who observes kashrut to participate in this experiment, we would have to determine that medical experimentation is to be defined as “medicine,” even though the experimental procedures and findings may not prove therapeutic for the individuals who participate in the test.

How then does our tradition define and understand the practice of medicine? While the Talmud itself is ambivalent, containing both negative[15] and positive[16] remarks about physicians and the healing arts, it does regard medicine as reshut,[17] a permitted activity, and later scholars raise this “permission” to the level of mitzvah, the commandment to save life.[18] This commandment, as we have seen, stands at the summit of Toraitic values; virtually every prohibition in the Torah is set aside for the sake of refu’ah. And refu’ah, moreover, is viewed as a “science,” an organized body of learning that is mastered by those specially trained in its accepted standards and procedures.[19] Like all science, medicine as we understand it today is an experimental enterprise. The many wonderful life-saving tools of contemporary medicine, the drugs and surgeries and therapies, could scarcely have been developed had they not been tested in accordance with the rigorous standards demanded by the scientific community. These tests, to be sure, do not always lead directly to the discovery or perfection of new drugs and therapies. It is in the nature of experimental science that hypotheses may be disproved, that theories may be challenged for lack of confirming evidence, and that practitioners determine that a particular direction of research is not a fruitful one. Yet precisely because these “failures” are part and parcel of the scientific method, they are an integral element of science itself. In our case, the science we call medicine requires experimentation of the sort described in our she’elah, whether or not that experiment succeeds in establishing the effectiveness of the cardiac drug. In the absence of such experimentation, the practice-that is to say, the science–of refu’ah could scarcely be conceived.

For this reason, too, we today cannot conceive of the mitzvah, the religious obligation of medicine, apart from the scientific approaches which structure and govern the practice.[20] Just as the science of medicine cannot exist apart from the experimental methods by which therapies are tested and perfected, so too would it be impossible to fulfill the mitzvah of refu’ah without them. We do not distinguish between the therapies of medicine on the one hand and the legitimate scientific procedures necessary to develop those therapies on the other. The term “medicine” includes both the application of life-saving measures and the development of those tools in accordance with the methods of experimental science.[21] Those patients who serve as subjects in this experiment are therefore participating in a legitimate medical procedure. Whether the tests succeed or fail to develop a new cardiac drug, the patients contribute toward the fulfillment of the goal of medicine as the Torah conceives it: the mitzvah of pikuach nefesh, the saving of life.[22]

Jews who observe kashrut may participate in the test described in our she’elah. Indeed, it is a mitzvah for them to do so.



  • BT Pesachim 25a-b. R. Yochanan’s declaration is part of the famous discussion (with partial parallels in Yoma 82a-b, Sanhedrin 74a, and Avodah Zarah 27a-b) of the sins that must never be committed, even for the sake of saving life. Idolatry is not to be practiced because one is commanded to “love Adonai your God…with all your life (bekhol nafshekha; Deut. 6:5)”, even at the cost of one’s life. Forbidden sexual relations (i.e., the list of the arayot in Leviticus 18) are to be avoided at all costs since the Torah compares them to murder (Deut. 22:26). And murder itself may never be resorted to, even to save one’s life, because it is possible that “the other man’s blood is redder”: one is in no position to determine that one’s own life is more valuable in God’s sight than that of one’s intended victim, and it is only such a judgment that would permit a murder in order to save one’s life.
  • Yad Yesodey Hatorah 5:6; SA YD 155:3.
  • BT Yoma 85b, on Lev. 18:5.
  • See M. Yoma 8:5-6; Yad, Ma’akhalot Asurot 14:14-16; and SA OC 618. These passages deal with feeding a sick person on Yom Kippur, and they make clear that the permit for feeding includes foodstuffs normally prohibited as tamey (impure).
  • See Lev. 19:23-25.
  • BT Pesachim 25b.
  • Yad Yesodey Hatorah 5:8; Sefer Hamordekhai, Pesachim, ch. 645, in the name of R. Eliezer b. Yoel Halevy (Ra’avyah); SA YD 155:3; Siftey Kohen ad loc., nos. 13-14; Resp. Ketav Sofer, OC, no. 111.
  • R. Yechiel Ya`akov Weinberg, Resp. Seridey Esh 2:59.
  • These positions are discussed by R. Yechezkel Landau (18th cent.) in Resp. Noda Bihudah 1:35.
  • Resp. Seridey Esh 2:59, end. On the “bitter substance” issue, see Yad, Yesodey Hatorah 5:8.
  • See Isserles, SA YD 87:10 and Arukh Hashulchan, YD 87, par. 43. On “new substance,” see R. Chaim Ozer Grodzinsky, Resp. Achiezer 4:11.
  • The best summary is that of R. Isaac Klein, Responsa and Halakhic Studies (New York: Ktav, 1975), 43-74. The issue with respect to cheese concerns rennet, a curdling agent drawn from the stomach wall of the animal. Gelatin is a problem because it might be made from the bones and skins of non-kosher animals.
  • See BT Menachot 21a and Chulin 120a.
  • Resp. Shevut Ya`akov 2:70. Reischer adds another argument in favor of his permit: the specific complaint for which the bocksblut is prescribed is “pain experienced in the internal organs,” which might easily be defined as a serious illness even if the physicians do not so regard it.
  • After Ex. 15:26, which describes God-and presumably not the physician-as the source of healing. The rabbis were also influenced by the biblical author’s condemnation of King Asa in II Chr. 16:12 (“in his illness he sought not God but rather physicians”). See BT Berakhot 10b and Pesachim 56a, where King Hezekiah is praised for hiding away a medical book so that people would learn to pray for healing rather than seek medical help. See also the prayer recorded in BT Berakhot 60a, bottom, and Rashi ad loc. s.v. she’ein darkan shel beney adam. For a concise statement of this position, one could hardly do better than M. Kiddushin 4:14: “the best physician is deserving of hell,” which Rashi (BT Kiddushin 82a, s.v. tov shebarof’im) explains in that the physician arrogantly regards himself, rather than God, as the author of the patient’s healing. It is Nachmanides, in his commentary to Lev. 26:11, who presents what may be the classic formulation of this perspective. God’s people, he writes, were never intended to be subject to the laws of the physical universe; rather, they were to be judged solely according to their moral deserts. The Israelites, however, rejected this arrangement by consulting physicians during time of illness; as a result of this lack of trust, God has left us to our desires and made us subject to natural law. While we now have no alternative but to engage in natural medicine as a response to illness, therefore, this fact constitutes a spiritual defeat for us.
  • See BT Bava Kama 46b (“one who is in pain should go to the physician”) and Sanhedrin 17b (“A Torah scholar should not live in a city that does not have these ten things…”), one of which is a physician (rofe). Rashi, along with R. Menachem Hameiri (Beit Habechirah, Sanhedrin 17b) define this rofe as a mohel, one who practices the art of ritual circumcision, rather than a “physician.” Maimonides, on the other hand, does not make this qualification (Yad, De`ot 4:23).
  • BT Bava Kama 85a, from Ex. 21:19.
  • The authorities differ as to the biblical source of this mitzvah. Nachmanides (Torat Ha’adam, Chavel ed., Jerusalem, 1964, 41-42) classifies medicine under the heading of pikuach nefesh (and see Tur and SA YD 336:1) , while Maimonides derives the commandment from Deut. 22:2, the obligation to restore lost objects, which the Rabbis (BT Sanhedrin 73a) extend to the saving of life (Maimonides, Commentary to M. Nedarim 4:4).
  • See SA YD 336:1: while each of us is responsible to fulfill the mitzvah of pikuach nefesh, none should practice medicine who is not an expert (baki) in its procedures and who is not licensed by the proper authorities.
  • To be sure, it was not always this way. Prior to the modern period, medicine was a traditional science; much like law, theology, and similar disciplines, one learned it through the reading of the authoritative texts of such luminaries as Hippocrates and Galen, combined with a period of apprenticeship to a master. It is this version of medical study which R. Moshe Feinstein (see note 22) cites approvingly in explaining how kohanim in former times could train to become physicians. Obviously, the science of medicine has progressed (a term which, in this context, we do not think is pejorative) to the point that it can no longer be taught in this manner.
  • We should note that many halakhic authorities do seem to draw such a distinction. While they define medicine as pikuach nefesh, they limit it strictly to the application of therapies to patients while excluding from its purview many of the procedures that are indispensable to the practice of medicine. For example, while Jewish law does not prohibit a kohen from practicing medicine, most Orthodox halakhists do forbid him to study medicine should this study require contact with cadavers, since the priest is not to defile himself by contact with corpses other than those of his close relatives (Lev. 21:1-3). See Kol Bo `al Aveilut, 81-84, Gesher Hachayim I, ch. 6, par. 1, note 4, and R. Moshe Feinstein, Resp. Igerot Moshe YD 3:155.
  • On a related issue, see Teshuvot for the Nineties, 381-389, no. 5755.11.


If needed, please consult Abbreviations used in CCAR Responsa.