I have about a year old blue bar ambilobe Panther chameleon that has always ate and run around but lately his eyes have started to sink in his grips been getting weak sleeps all day he keeps opening his mouth and refuses to eat anything and he's also getting very bright colors. he's in a 16 by 16 by 60 cage with a 50 watt heat lamp and a reptisun bulb I feed him crickets super worms and occasionally butterworms and I occasionally dust them with calcium and vitamins
There are several possibilities that lead to this, but we need more details to tease them apart.
How old is the ReptiSun bulb? If older than 6 months replace it. The UVB it produces drops off after that amount of use.
When you say you "occasionally" dust the insects with calcium and vitamins what do you mean? There is a specific schedule of dusting that is important to follow:
Dust with plain calcium (no added vitamin D3) daily.
Dust with calcium with added D3 twice a month.
Dust with a herp multivitamin twice a month.
What do you feed your insects? If they are not gutloaded correctly your cham isn't getting balanced nutrition which will add to the problems. Most pet shop "gutloads" are not great.
What are the cage humidity and temp cycles?
If you look at the top of this forum and find the sticky message "How to Ask for Help" there are questions designed to help us help you. Please post the answers. Either way, locate vets that jann suggests and get him to one. The vet will need the same information we do as well.