The Nature Zone SNZ59231 Appetite Plus Reptile Concentrated Solution is a natural appetite enhancer that comes in a 2-ounce bottle. It is designed to increase the appetite of finicky feeders or animals recovering from an illness or malnutrition. The solution contains Vitamin B-12, which has been shown to stimulate the appetite in most vertebrates. The solution also contains a proprietary blend of herbs and spices that are known to increase the appetite.