A suppository is a medication that is intended for rectal use only, and it takes an hour or longer to be fully absorbed into the body, reports MedicineNet.com. Individuals who have taken a suppository should avoid having a bowel movement during this period.
Glycerin is a suppository that relieves constipation by causing a bowel movement within 15 to 60 minutes after use. The side effects include stomach cramps, rectal irritation and rectal burning, says WebMD. Promethazine is a suppository that is used to treat nausea, vomiting and allergy symptoms. The side effects are blurred vision, constipation, dry mouth and dizziness, reports MedicineNet.com.