It is not clear from your question if the colon ulcerations were caused by the snake poison or they were discovered accidentally during the hospitalization. If the ulcers were caused by the snake poison, then they will be healed in time. If your husband is suffering from colitis ulcerative, then the situation is serious. Colitis ulcerative is a chronic inflammatory disease of the large intestine with an unknown etiology (probably an autoimmune disease). There is no current efficient treatment. Chronic bloody diarrhea is the main symptom, but some dangerous complications such as perforation or malignant alteration can also occur.