Serotonin agonists are used to treat migraines and chronic idopathic constipation (CIC). They work for migraines by stimulating serotonin receptors (chemical binding sites) in the brain, which blocks certain pain signals to the brain. They work for CIC by stimulating serotonin receptors in the colon, which helps stimulate muscle contractions in the bowel. Serotonin agonists come as oral tablets. Examples include prucalopride (Motegrity) for CIC and lasmiditan (Reyvow) for migraines.