Description

Tegaserod is a medication that belongs to a class of drugs called serotonin agonists. It was initially approved by the FDA in 2002 for the treatment of irritable bowel syndrome with constipation (IBS-C) in women. It was later withdrawn from the market in 2007 due to concerns about an increased risk of serious cardiovascular events, such as heart attack and stroke. It has since been reintroduced under a restricted-access program for a specific population.

Indication

Tegaserod is indicated for the treatment of Irritable Bowel Syndrome with Constipation (IBS-C) in adult women under 65 years of age who have no history of cardiovascular ischemic events (e.g., heart attack, stroke, transient ischemic attack, or angina). Its use is limited and requires a doctor’s prescription due to its restricted availability. The safety and effectiveness of tegaserod in men have not been established.

Mechanism of Action

Tegaserod is a selective partial agonist of the serotonin-4 (5−HT4​) receptor, which is found in the gastrointestinal tract, primarily in the enteric nervous system. By activating these receptors, tegaserod triggers the release of neurotransmitters, such as acetylcholine. This action has several effects on the gut:

• Stimulates Gastrointestinal Motility: It enhances the peristaltic reflex and increases intestinal secretion, which helps to accelerate the movement of stool through the bowels.
• Reduces Visceral Sensitivity: It moderates the sensitivity of the gut, which can help to alleviate symptoms like abdominal pain and discomfort.

In addition to being a 5−HT4​ receptor agonist, tegaserod is also a 5−HT2B​ receptor antagonist, which may contribute to its overall effects on the gastrointestinal system.