Hapigut 400 Tablet contains Rifaximin 400 mg, a broad-spectrum, non-systemic antibiotic primarily used to treat gastrointestinal infections caused by susceptible bacteria. Rifaximin acts by inhibiting bacterial RNA synthesis through binding to the beta-subunit of bacterial DNA-dependent RNA polymerase, thereby preventing bacterial replication and growth. Due to its minimal systemic absorption, Hapigut 400 is particularly effective in targeting infections localized within the gastrointestinal tract, such as travelers’ diarrhea caused by non-invasive strains of Escherichia coli, hepatic encephalopathy to reduce the risk of recurrent episodes by decreasing ammonia-producing gut bacteria, and irritable bowel syndrome with diarrhea (IBS-D) to alleviate symptoms. The medication is generally well tolerated, with a low incidence of systemic side effects due to its localized action. Hapigut 400 should be administered as prescribed by a healthcare professional, with dosage and duration tailored to the specific indication and patient condition. Caution is advised in patients with hypersensitivity to rifamycin derivatives. It is not recommended for systemic infections or severe hepatic impairment without medical supervision. Patients should complete the full course of therapy to prevent bacterial resistance. Hapigut 400 offers an effective therapeutic option for managing specific gastrointestinal bacterial infections with a favorable safety profile.