Treatments used for Symptoms of IBS :
Since the actual cause of IBS is unknown, the treatment focuses mainly on controlling and reliving the symptoms. Depending on the nature and extent of symptoms, your gastroenterologist may suggest medications like:
Fiber supplements for controlling constipation – psyllium (Metamucil) or
methylcellulose (Citrucel)
Anti diarrheal medications : ex:-loperamide (Imodium)
Anticholinergic and antispasmodic medications – Medications like Lyoscyamine (Levsin) and dicyclomine (Bentyl), can help relieve painful bowel spasms.
Antidepressants – low doses of tricyclic antidepressants and selective serotonin re-uptake inhibitors to relieve abdominal pain.

Lubiprostone (Amitiza) for people who have IBS-C to improve abdominal pain or discomfort and constipation symptoms.
Linaclotide (Linzess) for people who have IBS-C to relieve abdominal pain and increase how often you have bowel movements.
The antibiotic rifaximin to reduce bloating by treating small intestinal bacterial overgrowth. However, experts are still debating and researching the use of antibiotics to treat IBS.