Here you go. I have copied
The key points and insert here first. Then i included the link to the study. Lots of reading but I found it interesting

3 × 262 mg tablets po tid × eight weeks

Antidiarrheals

Bismuth subsalicylate
Bismuth subsalicylate is an over-the-counter agent used for various gastrointestinal complaints. It has been studied for the treatment of microscopic colitis, and been found to improve both clinical and histological activity of the disease over the short term, without significant adverse events (6,7). The long-term benefits of this medication are unproven, but it likely can be used effectively to treat patients with relapsing disease. There is a theoretical potential for bismuth toxicity with continuous use, so a regimen of intermittent use is preferred (8).
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2661290/