Q. Do you make a brocho when drinking water from a mineral spring that has therapeutic value and also has a good taste?

A. Poskim disagree if you drink water when you are not thirsty and you drink just for medicinal purposes, if you should recite a brocho. Some maintain that no brocho is recited, but you say a prayer for refuah. (Shaarei Halocho – Miluim 36, quoting Tzemach Tzedek). Others maintain that since after all the water is tasty, you should recite a blessing (Shoel Umeshiv 5: 23, Binyan Tziyon 10 and 3: 7, Sdei Chemed – Maareches Brochos 7). There is one opinion that even if the waters are not tasty you should express a blessing (Tehila Ledovid O.H. 204)
Horav Shlomo Miller’s Shlit’a opinion is that if someone feels a pleasant or desirable taste when drinking the mineral water (such as the bubbliness or effervescence of gas present or the flavor of the salts), he should recite a brocho even if he is not thirsty. The therapeutic value of the water is of no consequence.

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