Chapter 91:3
Non-Critical Illness on Shabbos
3. A person who has a slight toothache, but is not in great pain, should
not rinse his mouth on shabbos with vinegar or another liquid to alleviate
the discomfort, and then spit it out (1). Instead, he should rinse his
mouth and swallow it (2). Alternatively, he may dip bread in vinegar and
eat it in a normal manner.
Similarly, a person who feels discomfort in his throat should not gargle
with a liquid, and then spit it out. Rather, he should swallow it, and if
as a result he is cured, then so be it.
FOOTNOTES:
(1) If one rinses one's mouth and then spits out, it is obvious that one is
doing it for medicinal purposes. It is even forbidden to leave it in one's
mouth for a prolonged period, and then swallow it ( See HY 91:2 and Mishna
Berura 328:101).
(2) It is prohibited to swallow any liquid which people in the local area
don't usually swallow (Mishne Berura 328:105).
