Kit - we need more info to help you.
Please let us know what the temperature is in the animals' enclosure during the day and at night. It would be helpful to know the temperatures in both the hottest spot and in the coolest spot in the cage.
Next, what types of lights are you using (flourescent, incandescent, etc) and how long are they on each day?
What are you using as a heat source?
What is the humidity in the cage?
What size is the cage? What is it made of (an aquarium, a wooden structure with screened sides, a cardboard box...)?
What do you have in the cage (branches, shelves, plants, soil, woodchips, newspaper)?
How big is the water bowl?
What are you offering for food?
Did the vet take a fecal sample and check for parasites?
Answer these questions and someone here may be able to offer you some advice.
Also - to the person who mentioned food supplements - are you thinking of Walkabout Farm? You can find them at herpnutrition.com.
-Z