Q. I’m taking antibiotics and I also suffer from reflux and find it hard to fast, do I have to fast on the 17 of Tamuz?

A. Shulchan Aruch (O.H. 554: 6) rules that an ill person does not have to fast on the lesser days of ta’anis since the Sages did not institute fasting in cases of illness. Mishna Berura (ibid. 11) defines ill as one that is weak and in pain, even if not in a life-threatening situation. The Poskim debate whether there is a point for one in such condition to partially fast. Some maintain (Aruch Hashulchan 554:7, Kisvei Hagrach 45, Avnei Nezer O.H. 540) that since the Sages did not institute fasting, there is no mitzvah or reason to fast part of the day or eat less than the shiur (quantity needed to transgress.) Others opine that in principle the ta’anis remains in place (Maharam Shick O.H. 289 quoting Chasam Sofer.)

Horav Shlomo Miller’s Shlit’a opinion is that if one is not actually in pain although he has a medical condition or disease and is taking medicine, if his illness is controlled and fasting will not aggravate the ailment, after consulting with his doctor, he can fast for as long as he does not feel sick, experiences pain or becomes weaker than expected in a day of fasting.

All Poskim agree that even when permitted to eat one should not indulge in unnecessary delicacies and culinary treats in that day (Mishna Berura ibid. 5).

Rabbi A. Bartfeld as revised by Horav Shlomo Miller Shlit”a.