Medical on Rosh Chodesh
Question
I took a CAT scan this a.m. first they had to draw some blood I forgot it was Rosh Chodesh Is one allowed to take blood on RH?
Answer
Shalom!
Thank you for your question!
First of all, there is no such thing as “bloodletting” nowadays. The bloodletting of the Talmud was a procedure in which a lot of blood was removed from the body (at least 40%) based on medical beliefs of the time. These procedures are not done nowadays.
Furthermore, even when bloodletting was done, Rosh Chodesh or Erev Rosh Chodesh was never one of the problematic days to perform bloodletting. The problematic days for bloodletting were Mondays, Tuesdays, Thursdays, and Erev Yom Tov.
Again, this procedure does not exist nowadays and, hence there is nothing to worry about.
SOURCES: Shabbos 129b; Shu”t Harashba 1:413; Shulchan Aruch Harav, OC 468:22-23; Tzitz Eliezer 12:46