Q. Dear Rabbi: If someone had to take pills with some water during Tisha Beav as permitted by Halacha due to his medical condition, is he still considered as fasting and can still recite Anenu or get an Aliya LaTorah?
A. Mishna Berura (568: 5) rules that if one drank less than a Meloh Lugmav (or one cheekful) he is still considered as fasting and has to complete the Taanis.
A Meloh Lugmav is often referred to as Rov Revi’is or the majority of a Revi’is (about 1.27 fl. oz. or 38 ml lechumra).
Rabbi A. Bartfeld as revised by Horav Dovid Pam, Horav Aharon Miller and Horav
Chanoch Ehrentreu Shlit’a.