If one suffers from chronic constipation and IBS may they take a laxative on shabbos or Yom tov? They may be able to wait until after shabbos although taking the laxative may aid their oneg shabbos or Yom tov.
Taking a laxative on Shabbos or Yom Tov will depend on each individual case. The general rule is that is the constipation is incapacitating, then the person is considered choleh, and it may be taken, otherwise not. On a practical level, if you take the laxative before shabbos or yom tov, you shouldn’t have any constipation, ad IY”H you’ll enjoy you shabbos.