A hanging dripper system would help too. Hang it over a potted plant in the chameleons cage and let it drip on the leaves for a few hours a day.
Unsanitary conditions and parasitized insects can pass parasites and intestinal infections to your chameleon. Try to remove any fecal matter as soon as possible once a day and clean the entire cage every week or so. Only use prey items that have been raised by reputable dealers in sanitary conditions and only gut load them with fresh grains, vegetables, and fruits. Anything old and moldy that the prey items eat will be passed on to your chameleon too. Some people use wild caught prey items and those can carry mites and other parasites or be poisoned due to pesticides. Be cautious what you allow into the chameleon's cage and take out anything undesirable as soon as you notice it.