Offer your gerbil plenty of water: Oranges can also dehydrate gerbils, so make sure your gerbil has access to plenty of fresh water.
Feed your gerbil a healthy diet: A healthy diet for gerbils includes a variety of foods such as seeds, grains, vegetables, and fruits. Avoid giving your gerbil foods that are high in sugar or fat, as these can also cause health problems.
Take your gerbil to a vet if necessary: If you are concerned about your gerbil's health after it has eaten a tiny bit of orange, take your gerbil to a vet. The vet will be able to examine your gerbil and determine if there are any health problems that need to be treated.