The active ingredient in Natrapel Lemon Eucalyptus insect repellents is oil of lemon eucalyptus, made from the leaves of the lemon eucalyptus tree. Oil of lemon eucalyptus is the only naturally derived ingredient recommended by the CDC to repel insects. Lemon eucalyptus insect repellents can be used on the whole family and are safe for use on gear and clothing. Enjoy plant-based protection from mosquitoes and ticks with Natrapel Lemon Eucalyptus insect repellents.