Hello and welcome. My name is ***** ***** I'm a biologist with a special interest in reptiles. I'm sorry to hear of this problem.
I suspect you have been reading online about sugar baths and Vaseline. Those first aid measures are last ditch methods for lizard owners who don't want to see a vet. What they usually do is try to push the prolapse back in after using Vaseline. This is a temporary fix at best. Sometimes the Vaseline can even complicate things. I wouldn't apply any more. Trying to push the prolapse back in is even more likely to result in problems.
I'll give you the best first aid, but your dragon will need to see a vet as soon as one opens. Make a paste of some table sugar and water. Actually cover the prolapsed organ with it. Also place some of the paste on a clean paper towel, and set your dragon in it. If you prefer the sugar baths, make sure the sugar is very concentrated in the water. Sometimes this will cause the prolapse to go back into the body. If you want to use a lubricant, a water-based one, such as KY Jelly is a better choice. This is a first aid measure only, and you will need to take the dragon to a reptile vet who can treat him appropriately as soon as possible. This link will take you to a directory of reptile vets:
Even if the prolapse goes back in when you apply the sugar paste, it's important to see a vet. Once this happens, it will probably happen again, and a vet can take steps to prevent that. Your dragon may also need antibiotics to prevent infection.
If you have more questions, just let me know. I hope your dragon will be fine.
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