DEET, or N,N-diethyl-meta-toluamide, is the active ingredient in many insect repellents. It effectively repels a wide range of biting insects, including mosquitoes, midges, gnats, ticks and sandflies. DEET insect repellent can be applied to skin or clothing and is found in insect repellent sprays, lotions, wipes and wrist bands.
DEET is thought to work by interfering with an insect’s sensory receptors and hindering its ability to detect chemicals given off by humans and other mammals. If you are wearing a DEET insect repellent that is actively working, you are undetectable by any nearby biting insects.
Is DEET Effective?
DEET is scientifically proven to be effective against biting insects that spread serious diseases such as malaria, encephalitis and Lyme disease. The higher the concentration of DEET an insect repellent contains, the longer it provides protection from insect bites before reapplication is necessary.
According to the Centers for Disease Control and Prevention, an insect repellent containing 23.8 percent DEET may provide about 5 hours of protection against mosquito bites.
A product containing 20 percent DEET may give about 4 hours of protection. The duration of protection DEET insect repellent provides also depends on other factors such as temperature and water exposure.
Is DEET Safe?
DEET is safe for short-term human exposure and is registered for use as an insect repellent with the U.S. Environmental Protection Agency. DEET insect repellent is approved for use on both adults and children.
DEET is not expected to present a health risk as long as it is used according to label directions.
Safety guidelines include:
- Use the minimum amount of DEET necessary to cover skin
- Do not over-apply DEET
- Do not use DEET under clothing
- Do not apply DEET to sore or broken skin
- Wash DEET products off when they are not needed
- Avoid the eyes and mouth
- Do not swallow DEET
- Do not let young children apply DEET to themselves
- Do not spray DEET insect repellents directly on to the face
DEET insect repellent is sold in variable concentrations. When deciding which concentration of DEET to use, consider the length of time you will be outdoors, your risk of being bitten by insects and the prevalence of insect-borne diseases in your area.