Off! is a popular brand of insect repellent, produced and sold in the United States by the SC Johnson corporation. It comes in aerosol cans and is sprayed directly onto the skin of the human to be protected. A variety of products sold under the Off! label offer protection against mosquitoes, ticks, and other insect pests.
The active ingredient in Off! is N,N-diethyl-meta-toluamide, or DEET. The U.S. EPA has ruled that DEET is safe for occasional use, provided that it does not enter the mouth or eyes, touch mucus membranes, or remain on clothing for a prolonged period. Like most insect repellents, it presents a mild long-term health risk in exchange for immediate freedom from discomfort and insect-borne diseases.
If you only rarely find yourself in the woods, Off! is probably a safe and useful product. People who are exposed to insects every day should consider less toxic methods of protection, such as cedar, cinnamon, and heavy clothing.