The present disclosure provides for acid-resistant capsules comprising compositions, e.g., formulations, used for gastric, gastrointestinal and/or colonic treatments or lavage, e.g., orthostatic lavage, e.g., for inducing the purgation (e.g., cleansing) of a gastrointestinal (GI) tract, including a colon. Compositions of the invention are used for the stabilization, amelioration, treatment and/or prevention of constipation, for the treatment of abdominal pain, particularly non-specific abdominal pain, and diarrhea, including diarrhea caused by a drug side effect, a psychological condition, a disease or a condition such as Crohn's Disease, a poison, a toxin or an infection, e.g., a toxin-mediated traveler's diarrhea, or C. difficile or the pseudo-membranous colitis associated with this infection.