Although they're very effective, experts are torn on insect repellents containing the controversial chemical DEET. An active ingredient in many insect repellents, DEET works by blocking the odors that attract insects to humans. In high concentrations, DEET has been proven to damage clothing, paint finishes and even plastic. It also has a very strong scent, which most reviewers find unpleasant. Many alternatives to DEET have appeared on the market, but no other alternative insect repellent is shown to be as effective, especially for warding off mosquitoes.
Cutter's the best spray repellent
Reviewers say Cutter Advanced (*Est. $6 for 6 oz.) is the best mosquito repellent overall. Its active ingredient is synthetic picaridin, which works in a similar capacity to DEET but is considered safer to use. Reviewers like this product because it's odorless and doesn't leave skin feeling sticky. While repellents that contain DEET are not recommended for small children, Cutter Advanced (and other repellents made with picaridin) can be used on babies as young as 2 months old. Cutter Advanced is effective for up to 2.5 hours, and can be reapplied up to three times per day.
Long-lasting insect repellent lotion
If you plan on being outdoors for an extended period of time, reviewers recommend 3M Ultrathon Insect Repellent 12 Lotion (*Est. $8.50 for 2 oz.). It is water-resistant and protects against mosquitoes, ticks and biting flies. The high concentration of DEET (34 percent) allows it to last up to five hours. Since 3M Ultrathon uses a special form of DEET that doesn't absorb as easily into the skin, experts say it's safer to use. Like any product that contains DEET, it needs to be washed off before going indoors and it should never be used on babies.
Natural alternative to chemical repellents
For those who prefer a natural insect repellent, reviewers say Repel Lemon Eucalyptus (*Est. $7.50 for 4 oz.) provides long-lasting protection against mosquitoes, gnats and ticks. Since it contains plant-based ingredients, it won't damage plastic or synthetics, but it can stain leather. On the downside, Repel Lemon Eucalyptus can't be used on children under the age of three. It should not be applied more than twice per day -- this shouldn't be a drawback for most users considering one application will last about four to six hours.
Kid-safe insect repellent
Bite Blocker (*Est. $8.50 for 4.7 oz.) is deemed the safest natural insect repellent for children. It is effective against mosquitoes, ticks and black flies. Made with plant-based ingredients such as soybean and geranium oil, Bite Blocker outshines most other natural insect repellents in performance tests. However, its protection time (90 minutes to two hours) is significantly less than Repel Lemon Eucalyptus, which can last from four to six hours. Its greatest advantage is that it is safe to use on children as young as 2 months old.