Insect bites are common an most often harmless. Bites from insects may cause discomfort, allergic reaction, prolonged itching, and occasionally disease (e.g. Lyme Disease and West Nile VIrus) may be spread by bites from mosquitoes, ticks, and other insects. Prevention and limiting exposures to insects is the best way to limit the consequences of such bites and stings.
- When possible, avoid use of scented soaps, perfumes, hair sprays and clothing with dark or bright colors. Neutral colors are best. Cover skin with long pants and sleeves. Clothing (not skin) treated with permethrin may be helpful. Mosquito netting may be helpful over infant carriers.
- Avoid areas where mosquitoes congregate, such as any standing water.
- DEET (N,N-diethyl-m-toluamide or N, N-diethyl-3-methylbenzamide) is currently the safest and most effective insect repellent on the market. The concentration and form affect the efficacy and duration of action.
Deet Recommendations
- DEET should not be applied more than once a day.
- The American Academy of Pediatrics does not recommend use of DEET for infants 2 months old or less.
- The AAP also does not recommend using products combining DEET and sunscreen. DEET may be applied 30-60 minutes after sunscreen.
- Increasing the concentration of DEET increases it duration of protection. A product containing nearly 24% DEET provides about 5 hours of protection (OFF! Deep Woods, 23.8%), while another containing under 7% DEET lasts about 2 hours (OFF! Skintastic, 6.67%). Concentrations vary from product to product.
- Products over 30% concentration have little added benefit are not recommended.
- DEET is not effective when not directly applied to clothing or exposed skin. Wristbands containing any repellent do not appear to work.
- Avoid applying DEET to children's wounds, inflamed areas or hands. Ingestion and heavy application may lead to toxicity.
- DEET will wash off when wet and should be removed after returning inside.
- Other non-DEET and plant based products appear to have modest to little effect in preventing insect bites.
- Soybean oil appears to be the most effective plant-based product lasting 1 1/2 hours (Bite Blocker for Kids, 2% soybean oil), equal to 4.75% DEET (OFF! Skintastic for Kids).
- Other products including citronella, peppermint, cedar, lemon grass and geranium extracts appear to last only 3 to 20 minutes.
References
Fradin MS, Day JF. Comparative efficacy of insect repellents against mosquito bites. N Engl J Med. 2002;347(1):13-8.