What is Constipation? Constipation is infrequent or difficult passage of stool or feces and is typically a temporary condition. Feces accumulate in the colon (large intestine). Many constipated cats experience straining or pain when attempting to defecate. Obstipation, a severe form of constipation, is often associated with a serious, permanent, or irreversible medical condition. One of the major functions of the colon is water absorption, so sometimes the retained stool beco