Q. I'm a Frum physician that was called out on Shabbat to travel and attend a suicidal woman that poisoned herself by swallowing a large amount of pills. Since this person had given up on her own life, as can be read in the letter she left, did I have to desecrate Shabbos on her behalf (I was close by)? Could I have referred her to other medics and emergency services?
A. Hochmas Shlomo (O.H. 329: 1) debates the issue and leans to opine that one should not desecrate Shabbos to save one that wants to terminate his life.
Minchas Chinuch (Kometz Lemincho 237) compares the above to the obligation of returning an item lost (Hashovas Aveida), that does not apply when the owner willingly wishes to get rid of his property. He goes even further and mentions that even when not Shabbos, one is not required to interfere.
However, other Poskim disagree. (Birkei Yosef - O.H. 301: 6), Maharil Diskin - Tesh. 2: 5:34, Chelkas Yaakov 1: 72, Tzitz Eliezer 8: 15, and others. See also Igrois Moshe (O.H. 1: 127 - Y.D. 2: 174).
Out of my personal experience since having attended an average of 2 or 3 suicides a year while being Chief Rabbi in Mexico, the vast majority are people who attempt or commit suicide are in a relatively extreme degree of distress, pain and fear and should therefore not be considered at that time to be "Lodaas" or willing and conscious of their actions.
See a similar opinion in Nishmas Avrohom (p. 169).
Horav Shlomo Miller’s Shlit”a opinion is also similar and anyone should do whatever they can to save that life even during Shabbos.
Rabbi A. Bartfeld as advised by Horav Shlomo Miller and Horav Aharon Miller Shlit'a