Can you have a poop in an adult diaper?

Yes and no. It depends on the diaper. Technically you can mess (poop) any diaper, but with some diapers it would be no different then messing your pants. Most store brand diapers are not designed for fecal incontinence, as they are designed only for bladder leakage. For example, you would not want to mess any of the "Depends" diapers your going to find in a store.

If you need/want a diaper to handle fecal incontinence start with good quality "Fitted Brief" type diaper (like a baby diaper only bigger). I have learned over my life that a good quality diaper is 10 times better then a poor quality diaper, so the cost is well worth it. When I have an emergency and have to buy any of the brands of diaper that are in stores, I end up needing 5 or 6 in a day. When I buy something like Dry 24/7 or Abena from a medical supply company, I need 2 a day. So they may cost more, but in the end you use alot less, and have less accidents. I buy from xpmedical.com