Pancreatic Enzyme Dosing Calculator

Pancreatic enzyme replacement therapy (PERT) dosing for exocrine pancreatic insufficiency is conventionally expressed in lipase units per kilogram of body weight per meal. The American College of Gastroenterology's 2020 chronic pancreatitis clinical guideline (Gardner et al.) defines the two ends of that range -- 500 units/kg/meal as a starting dose and 2,500 units/kg/meal as the maximum for a single meal -- and this calculator offers two additional intermediate rungs, 1,000 and 1,500 units/kg/meal, as its own interpolated step-up points between those two published bounds, not as separately published guideline figures. Weight and the selected dosing level are the two direct drivers of the per-meal dose -- the same dosing level applied to a larger patient always produces a larger unit total, and the same weight dosed at a higher level does too -- so neither one is fixed as more important than the other; which one swings the result more depends on where the other is set, especially once the 40,000-unit adult floor and the fat-based cross-check are in play. Guidelines also specify a practical floor for adults -- most adult patients need at least 40,000 lipase units per meal regardless of what a pure weight-based calculation would suggest for a small or low-weight adult -- but that floor is not a pediatric dosing rule. Pediatric PERT is dosed strictly per kilogram, governed by the same 2,500 units/kg/meal and 10,000 units/kg/day maximums that apply throughout this calculator's full 3-250 kg range, so this tool only applies the flat 40,000-unit floor at 40 kg and above -- a conventional pediatric-to-adult dosing transition weight -- rather than forcing an adult minimum onto a child's per-kg dose.

As a cross-check, the calculator also computes an alternative fat-based dose (a mid-range 2,000 lipase units per gram of dietary fat, within the published 500-4,000 range) and recommends whichever of the weight-based or fat-based estimate is higher; at typical meal fat content, the weight-based figure is usually the larger of the two, so fat intake per meal often has no effect on the recommended dose unless fat intake is unusually high. Neither the number of meals or snacks per day, nor which capsule strength is selected, changes the recommended per-meal dose before the safety cap is applied -- those inputs affect how that dose is divided into a daily total and a capsule count. A hard safety ceiling of 10,000 lipase units per kilogram per day caps the daily total, consistent with published maximum daily dosing limits and the fibrosing-colonopathy risk that ceiling exists to avoid. When a meal-and-snack plan would exceed that daily ceiling, the calculator scales the displayed per-meal and per-snack doses -- and the capsule counts built from them -- down together, so the capsule regimen shown never recommends more than the safety maximum, even though discrete capsule sizes mean the actual rounded-up capsule total can still land slightly above the target.