“…There are [haredi rabbinic] opinions that state that a choleh [ill person], who is not currently in danger and is eating only to prevent potential danger, should begin receiving nutrition via an IV from before the onset of Yom Kippur.…”
The rabbis of Israel’s Ichud (United) Hatzalah released a Yom Kippur fact sheet for ill people that explains how the halakhic (Orthodox Jewish law) requirement of fasting on Yom Kippur should be handled. Ill people whose ives are endangered by fasting are exempt from fasting under halakha, but Ashkenazi haredi rabbis have added all sorts of ever-increasing requirements and caveats along with work-arounds to that blanket exemption, many of which are dangerous – especially this, from the United Hatzalah flyer:
“…There are [haredi rabbinic] opinions that state that a choleh [ill person], who is not currently in danger and is eating only to prevent potential danger, should begin receiving nutrition via an IV from before the onset of Yom Kippur.…”
The idea that getting an IV is a safe alternative to eating for the vast majority of seriously ill people is false. An IV introduces the possibility of sepsis, a system-wide infection that can be – and often is – fatal in elderly people even if they aren't ill. Yet people do this because they and their rabbis lack the education to understand the science and the dangers, and because doctors beholden to the haredi community improperly indulge them.
Rabbi Shlomo Zalman Auerbach, arguably the last truly great non-hasidic Ashkenazi haredi decisor of halakha in Israel, found a way to rule against this type of dangerous practice without raising the issue of the danger itself.
Sefardi haredi Rabbi Eli Monsur writes:
“…An interesting question arises in the case of an ill patient who needs to eat or drink on Yom Kippur but has the option of receiving his needed nutrients via intravenous. Feeding via intravenous does not violate the prohibition against eating on Yom Kippur, and thus, seemingly, this option should be utilized whenever possible to enable patients to observe the Yom Kippur fast without endangering their health. However, Rav Shlomo Zalman Auerbach (Israel, 1910-1995) ruled that to the contrary, an ill patient who needs to eat on Yom Kippur should eat normally, and not be fed via intravenous. Rav Shlomo Zalman noted that if we require a patient to pursue the option of intravenous, he or other people may mistakenly conclude that eating is forbidden on Yom Kippur even for ill patients, except via intravenous. As a result, in situations where intravenous is not an option, they will refuse to eat and thereby endanger their health. It is vitally important for people to realize that eating is permissible on Yom Kippur when it is medically necessary, as determined by a competent and reliable healthcare professional, and not to give the impression that even seriously ill patients must fast. Therefore, Rav Shlomo Zalman ruled, ill patients should not be given intravenous instead of food on Yom Kippur. This ruling is cited approvingly by Hacham Ovadia Yosef. As such, one should not try to “outsmart” Halacha by using intravenous instead of food on Yom Kippur; in situations where Halacha allows eating on Yom Kippur, the patient should eat, and not utilize an intravenous.
(Based on Yalkut Yosef – Yamim Noraim, p. 371)…”
Be that as it may, the reality is using an IV for no medically required purpose other than to allow a person to fast on Yom Kippur (or another religious fast day) should be against halakha for several reasons, most importantly the danger it poses to the lives of the frail (and often elderly) people who do it. Haredi rabbis should publicly denounce the practice now before another person is unnecessarily sickened or dies.