Hi hopingToFindCure. Flaygyl can be a good med for the cyst form, but from what I understand it should be started at a low dose and built up over time. When taking Flagyl, make sure you do not have alcohol of any kind (including mouthwash etc.) or it can make you very sick. It can have a bad taste when you swallow it. Some people find that coating it with olive oil helps.
I took Tinidazole which is similar to Flagyl but is supposed to be easier to tolerate.
I have a an article about Flagyl written by a PhD that I can email to you if you like. It is too long to post here, and the link is no longer valid.