Hello,
I’m sorry to hear about your cat. Without knowing all of the pertinent details, if you feel like you have tried and done everything (like canned food only, adding laxatives and encouraging and promoting as much activity as possible) and you are still not able to get the colon moving properly then the best option is a surgery called a subtotal colectomy (removing the colon ). It is generally agreed upon that a true mega colon cat is only treatable by this surgery.
I hope this helps and good luck.
Hello
I’m sorry to hear about your cat.
I think that you need to find a veterinarian or a veterinary technician who can show you how to do this. I would also recommend you start gentle physical therapy and feed canned food to keep the feces soft and able to pass more easily.