Amoebic infection occurs through poor standards of personal and community hygiene. The cysts are transmitted through the faeco-oral route and if you are getting repeated instances of amoebic dysentery, then you are acquiring the infestation through contaminated food or drink. I would suggest that you maintain high standards of personal hygiene. Don't eat at roadside places, drink clean water and avoid restaurants of low hygiene standards.
Presence of cysts of Entamoeba in the stool does not need any treatment, and over a period of time, the body eradicates the cysts. You only need treatment if ova of EH have been detected in your stools.
Diloxanide Furoate 500mg three times a day for 7 days will treat the cysts. Recurrent infection is only seen in persons who are immunocompromised.