DEAR DOCTOR K:
Which ingredients should I look for in a mosquito repellent? Are there any I shouldn’t use on my kids?
Ah, summer. Time for relaxing, playing outside, going to the beach — and mosquitoes. The itchiness from the bites can be maddening. And these tiny, annoying insects can carry serious illnesses, such as West Nile virus and Eastern equine encephalitis.
Many people worry that insect repellents themselves are dangerous. However, used properly, they are quite safe. It is particularly important to use insect repellents carefully, as described on their labels, for certain groups of people. This includes children, pregnant women, and people who work outdoors and therefore use insect repellent every day. These people may be more vulnerable to adverse effects.
Here’s a look at ingredients that will help keep mosquitoes away:
- DEET. This is the most commonly used repellent — and the most effective. The stronger the concentration of DEET in a product, the longer it will protect you. The American Academy of Pediatrics has said that it is safe to use products with up to 30 percent DEET.
- PICARIDIN. This repellent, which is also applied to your skin, is less widely available, but is also effective.
- LEMON EUCALYPTUS OIL. This plant-based repellent should not be used on children under 3 years of age. It is about as effective as low concentrations of DEET and is found in sprays and lotions.
- IR3535. This ingredient is not widely available in the United States.
- PERMETHRIN. This repellent works well, but shouldn’t be used on the skin — just on clothing or mosquito netting.
There are several other mosquito repellents on the market, but they are not as effective as the ones I’ve discussed.
Just as important as which repellents you use is how you use them. Here are some tips:
- Don’t use insect repellents on infants younger than 2 months old. (You can put mosquito netting over a baby carrier.)
- When you use spray repellent (rather than a cream) on your skin, clothing or mosquito netting, apply it outdoors, not indoors. That way, you won’t breathe it in (or get it on household surfaces).
- Don’t spray a repellent directly on your face. Instead, spray it on your hand and then rub some on your face.
- When you use a spray repellent, don’t overdo it: You need only a little, and using more is not necessarily better.
- Don’t reapply repellent unless you are outside for more than six hours or so.
Finally, take steps to avoid mosquitoes in the first place. Mosquitoes are most abundant between dusk and dawn, so try to be indoors at those time. If you are going to be outside, wear lightweight, long-sleeved tops and long pants sprayed with repellent.
Mosquitoes lay their eggs in standing water. Make it a habit to dump out buckets or kiddie pools at the end of each day.