Unless the eye problem that your chameleon is experiencing could be something other than hypovitaminosis A, so I do recommend that you consider taking your chameleon in to be evaluated by a qualified herp veterinarian as soon as possible. It may take several weeks before the positive effects of beta-carotene supplementation(more gutload) become evident, so I wouldn’t advise waiting that length of time to see if vitamin supplementation is helping. We are each only given one pair of eyes and they are irreplaceable, and a blind chameleon will probably not thrive or even survive, as its hunting skills will be negligible. I have heard of an owner that hand-fed a blind chameleon twice a day for its entire life after it became blind, but that is a huge commitment. With the best-case scenario, your herp vet can diagnose the problem and prescribe appropriate medication, either topically (into the eye or eyes) and/or systemic therapy.