Background: Irritable bowel syndrome (IBS) is a common and relapsing functional bowel disorder. This disease has a substantial global burden and is associated with significant disability and high costs that adversely affects the health related quality of life of large population worldwide. Aims and Objective: We studied the efficacy and tolerability of bulk laxative plus probiotic and prebiotic in the treatment of constipation associated IBS (IBS-C) in Indian patients. Materials and Methods: Eighty patients with symptoms of IBS-C were enrolled in a post-marketing surveillance, multicentre, open label, non-randomized, noncomparative study where EVAQ-P -combination of fiber (psylliun husk/Ispaghula, probiotic and prebiotic) was given BID for 6 weeks. The symptoms were assessed at baseline, and after completion of 2, 4 and 6 weeks of therapy. Results: Results showed a significant trend (p < 0.0001) of improvement from week 2 for abdominal pain, abdominal fullness, defecation frequency, straining during defecation, constipation and subject global assessment of relief (SGA). Approximately 6% patients showed flatulence (mild) as a treatment emergent side effect. Conclusion: Combination of ispaghula along with a blend of probiotics and prebiotic twice daily for 6 weeks is efficacious, safe, and well-tolerated in IBS-C patients.