You asked

How safe is it to use DEET on infants?

Infants under two months of age should not be exposed to any type of mosquito repellent, under any circumstances. Infant skin is very permeable and does not become similar to that of an adult before they have reached this age. To apply chemical products at this young age may cause serious skin damage. However, infants under two months should be protected from outdoor pests by dressing them in long sleeved/legged, light coloured clothing. Avoid bright or dark colours or flowery prints, as these attract insects. If there is a concern about heavy mosquito infestation, then the infant should be kept indoors.

DEET is a dangerous, but effective chemical found in mosquito repellents. Following a few simple guidelines will help to protect and keep your infant safe, if you feel that you must use a product containing DEET, once the infant has reached the age of two months.

Don't use products that contain both the repellent DEET and a sunscreen. Sunscreens need to be applied frequently because they can be easily washed off. DEET itself is not water-soluble and will last up to 8 hours. Repeatedly applying a combination product increases the potentially toxic effects of DEET.

Apply DEET sparingly on exposed skin and never under clothing. Don't use DEET on infant hands, or apply to areas around the eyes and mouth. Never apply DEET over cuts, scrapes or irritated skin. Avoid spraying it in enclosed areas and do not use DEET anywhere near food.

There are newer insecticides on the market, but although their track record is not as convincing as DEET's, they may be safer to use with infants and small children. The new DEET free repellents have been proven effect against insect bites, but their effectiveness wears off quickly requiring more frequent applications.

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