How long has it been there on his eye ? What kind of cage do you have ? What kind of light do you use ? How do you give him water ? How often to you handle him ? And how old is he ? I have a somewhat similar problem my female veiled chameleon is about 4-5 months old and on her right eye she has like a bulge or a bumb that appears to be under her eyeball or actually in her eye . I catch her scratching it against her branches in her house and has even tried to scratch it on my finger .