Where can I buy this and what is it usually for?

I am a strong proponent of probiotics - lactic bacteria.

It not only helps with your problem which may be incidental but would generally ensure a healthy digestive system. What it does is to replenish the GI tract with friendly flora to prevent harmful and even pathogenic bacteria from causing digestive disorders or problems. This disorders prevents the GI tract from getting the nutrients from food consumed leading to malabsorption and "malnutrition"?

A good probiotic should have a sure bacteria count (revival rate) and should preferably be live bacteria. It should have multi-strains of bacteria containing colonizing (permanent) strains. Different bacteria work at different areas of the GI tract and the colonizing strains prevent recurrence of the problem. The bacteria needs to be protected from the strong stomach acids when ingested as well so that it can be properly delivered to the intestines where the bacteria works best.

What is equally important is diet, lots and lots of water and exercise! If you are active and do not do a sedentary job, then you might be alright, even walking daily is good. The water helps the body get rid of waste and toxins effectively and I believe prevents "stones" in the organs too.

I hope this is useful and helpful info.

Take care