Glycerin suppositories are a medicine placed in the rectum to produce easier bowel movements when mild or moderate constipation is present. They come in a torpedo-shaped capsule, which has an outer layer of degradable gelatin that contains a dose of glycerin. This substance has several effects on the bowels. It helps to absorb water, which softens the stool, it stimulates the lining of the rectum so the urge to empty the bowels occurs, and it provides lubrication that makes it easier to pass stool without much straining. Glycerin suppositories are generally mild, but are meant for short-term use only.
Unlike laxatives that are taken orally, glycerin suppositories are inserted in the rectum. Generally, people are advised to use a glove coated with a water-based lubricant to push the suppository well into the rectum, and then to hold it in place for about a minute to prevent its expulsion. It can be helpful to lie down on the side and clench the anal muscles for several minutes after use, and it’s suggested people wait at least 15 minutes before using the bathroom to get the best effect.
This can be challenging because the urge to “go” gets strong when a suppository is in place. It’s especially difficult or impossible to control this urge in babies, young children, or in adults with diminished mental capacity. Still, even if people use the toilet before the 15 minutes are up, they may retain some of the benefits of the suppository and constipation could alleviated.
Generally, glycerin suppositories only work to address constipation in the lower bowel. If the blockage is in the upper gastrointestinal areas, these won’t work. They’re best suited if fecal matter in the lower bowel is hardened and difficult to pass. Oral laxatives may be preferred when fecal matter isn’t present in the colon, and bowel movements have been absent for several days. People should get advice from doctors on which laxatives are most appropriate.
Concern exists that overuse of glycerin suppositories may create dependence, where people find it very difficult to have bowel movements without them. In most circumstances, doctors won’t prescribe or recommend suppository laxatives for more than a week. Situations in which they might be prescribed include incidences of uncomfortable but relatively mild constipation in infants, children, and adults. They may be recommended after labor and delivery because they eliminate the need to strain. Oral glycerin could be recommended instead and has similar beneficial effects, with the advantage that taking an oral medication is often preferred to anal insertion.
