This study aimed to evaluate the effectiveness of oral atropine in the management of IHPS. Cases were diagnosed clinically and confirmed sonographically. Atropine was given orally from the outset at a dose of 0.18 mg/kg/day in eight divided doses, increased daily by 1/4th of the commencing dose till vomiting ceased. Ultrasonographic evaluation of pyloric muscle thickness and length was done at the commencement of treatment, after completion of treatment and at 3, 6, 9, 12 and 15 months follow up. Oral atropine was effective in 11/12 (91.06%) cases. Vomiting ceased in 14 to 21 days in all cases. One case required initial 7 days of i.v. treatment followed by 18 days oral treatment to stop vomiting. USG evidence of normalization of pylorus was observed in all these cases, 3-15 months after completion of treatment. We conclude that oral atropine proved to be a simple, effective, safe, very cheap and acceptable treatment option for IHPS.