Laxatives are medications used to relieve constipation by promoting bowel movements. There are many different types of laxatives. Some are intended to gradually promote regularity over a period of time whereas others work quickly to trigger bowel movements within hours or even minutes. Some fiber-rich foods such as bran or fruits with sorbitol (a crystalline alcohol) also have laxative effects.

Physicians may also instruct patients to take laxatives prior to certain medical procedures, such as a colonoscopy, which helps detect the presence of colon cancer.

Bowel movements occur naturally at different frequencies for different people. Some people may have as many as three bowel movements a day whereas others normally have as few as three bowel movements per week. However, several factors can interrupt a patient’s pattern or ability to have normal bowel movements. These include poor diet, physical inactivity, pregnancy, illness and stress.

Physicians usually prefer that patients try other methods of promoting regularity before using medications. These may include eating a fiber-rich diet, drinking plenty of fluids and exercising. However, in some cases laxatives may be the best alternative to treat conditions such as persistent constipation.

In most cases, laxatives are available in over-the-counter formulations. However, some laxatives are available only by prescription. Oral laxatives are available in liquid, wafer, tablet, gum, powder and granule forms. Rectal laxatives – which are usually intended to produce a bowel movement in a short period of time – are available as suppositories and enemas.

Patients who take laxatives are urged to remember that the medications can have negative side effects. For instance, patients who use certain laxatives too often may develop lazy bowel syndrome, in which the bowels fail to properly function without the aid of laxatives. In addition, some people may abuse laxatives, such as patients with bulimia nervosa who use laxatives to help maintain their body weight.