How Do Selective 5-HT3 Receptor Antagonists Work?

Selective 5-HT3 receptor antagonists are a class of medication that mainly aims to treat symptoms of irritable bowel syndrome (IBS).

5-HT3 receptors are mainly found in the brain and intestinal cells. When activated, they release a neurohormone called serotonin, which regulates:

• Passage of food from the mouth to the anus (gut motility)
• Intestinal secretions
• Local stimulation of smooth muscle in the intestine to cause contractions

People with IBS, who have diarrhea as a symptom, have increased serotonin levels found in their blood that can increase bowel reactions like cramps and diarrhea.

Selective 5-HT3 receptor antagonists prevent the binding of serotonin to 5-HT3 receptors in the intestine and help to:

• Slow gut motility
• Delay the passage of food through the colon and small intestine
• Control bowel urgency
• Improve bowel function
• Relieve cramps associated with diarrhea

Thus, 5-HT3 receptor antagonist drugs are useful to treat diarrhea-predominant IBS.

• Selective 5-HT3 receptor antagonists are mainly effective in treating diarrhea-predominant IBS in females.
• Some 5-HT3 receptor antagonists are used to treat chemotherapy-induced nausea and vomiting.

Selective 5-HT3 receptor antagonists, when taken orally, can cause some of these side effects:

• Constipation
• Nausea
• Abdominal pain
• Headache
• Fatigue
• Malaise
• Bloating
• Muscle spasm
• Cough
• Piles

The information contained herein is not intended to cover all possible side effects, precautions, warnings, drug interactions, allergic reactions, or adverse effects. Check with your doctor or pharmacist to make sure these drugs do not cause any harm when you take them along with other medicines. Never stop taking your medication and never change your dose or frequency without consulting your doctor.

Generic and brand names of selective 5-HT3 receptor antagonists include:

• Alosetron
• Lotronex