I recall the nurses in the hospital used a combination of 3 laxatives to control the stool. They certainly wanted to avoid the constipation, and, if anything, be on the softer side. (And this was the only type of medications that nurses could dial.)
Was also sent home with two of these laxatives, for the same reason. Only remember one -- senna (OTC).
Would highly recommend the pre-surgery consumption of carbo-hydrate drink, as directed. It helps restart the stomach
after the surgery.
Believe the walking also helps -- as if you didn't have enough reasons for doing it

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