Methods, pharmaceutical formulations, and kits are provided for using capsaicin to effectuate voluntary defecation in mammals who cannot defecate without external invasion of the bowel or those who defecate involuntarily (i.e., those having fecal incontinence). The pharmaceutical formulations and kits can also be useful for inducing defecation in mammals that do not have defecation dysfunction such as, for example, in a person who is unconscious and may defecate unconsciously or in a pet at a convenient location at a specific time. The methods and compositions provide patients with defecation dysfunction control over when and where they defecate.