It’s that time of year again when the bugs start to return from their “off season vacations” and pediatricians start to see children who are suffering from uncomfortable bug bites.
The best way to prevent bites from the myriad of insects including mosquitoes, mites, chiggers, flies and fleas is by using an insect repellent. Insect repellents do not prevent bites from stinging insects such as bees, hornets and wasps. The AAP recommends using bug sprays in children who are older than 2 months of age when necessary for preventing insect bites during outdoor activities. The most common insect repellent is DEET, a chemical that has been studied for over 50 years. Most of the OTC bug sprays contain DEET in different strengths. The higher the concentration of DEET, which typically ranges from 5 – 30 %, the greater the protection and length of effectiveness. I usually recommend starting with the lowest concentration of DEET, which typically provides protection for 1-2 hours, and use a higher concentration as needed for longer protection.
The number of bites a child receives and their reaction to bites are different in all children, so each child may need a different concentration of DEET to be effective. With concentrations of DEET above 50% (not recommended for children), the effectiveness and duration of protection actually plateaus, so there is really no benefit from higher concentrations.
Another product approved for use in the U.S. about 5 years ago is picardin. Picardin provides similar protection in both duration and effect to DEET. Cutter, Skin So Soft and Off all have some products containing 7-10% picardin. The advantage to picardin containing products is that they are odorless (unlike DEET) and do not feel as greasy on the skin and are less likely to cause skin irritation and damage to fabrics . With all products you must read the labels to see what you are getting. There has been some recent data on the use of natural products such as oil of eucalyptus which the CDC has found to be comparable in its duration of effectiveness in preventing mosquito bites, to lower concentrations of DEET. It may also work well against ticks (Repel).
Eucalyptus oil may be poisonous if ingested in large quantities and should not be used in children younger than 3 years of age. Other studies have found that 2% soybean oil (Bite Blocker for Kids) has similar levels of protection to products containing 5-15% DEET, and may provide up to 90 minutes of protection from mosquitoes. This may be a useful product for short term exposures. Chemical repellents containing permethrin kill ticks on contact but should never be applied to the skin, but may be applied to clothing. Insect repellents should not be reapplied throughout the day, as is sunscreen. Parents should be instructed to spray the insect repellent on their hands first and then apply to their child and do not apply to the areas around the nose and mouth.
It is a good idea to wash the repellents off with soap and water at the end of the day. That’s your daily dose for today. We’ll chat again tomorrow.