With how bad things are out there and tick populations blossoming, we're getting inundated with questions about tick repellents, which ones work, which ones don't - and more. So here is our attempt at answering all of those questions!
To start out, let's begin with stating that the only repellents that we wholeheartedly believe in (after doing much research) are: Permethrin (for clothing), Picaridin, and DEET (20-30%). Permethrin is a direct-contact insecticide, and DEET being a repellent that temporarily blocks the neuron receptors that detect CO2.
Permethrin is virtually non-toxic to humans and no systemic effects have been reported. In EPA and FDA tests, it was uncommon to have any skin reddening, rash or other irritation. When used as a repellent, permethrin is applied to exterior clothing where it dries and bonds to the cloth fiber. This water-based formula is non-staining, odorless and has exceptional resistance to degradation by sunlight (UV), heat and water. Although permethrin is approved for skin application under certain circumstances such as head lice formulas, it is not applied to skin as a repellent. Permethrin does not bond to skin (stick) and is quickly deactivated by skin's esterase action into inactive compounds. Because of these attributes permethrin offers no repellent benefit on skin. It is only effective when used as a clothing treatment.
Deactivation of permethrin on skin occurs in approximately 20 minutes; however, when placed on clothing, it tends to last up to 6 weeks and even lasts through weekly launderings. With the long history of success permethrin has achieved, it is best not to second guess these extraordinary results. By following the directions provided on the product you can be assured of results that achieve protection at or near 100%. Any variation of instructions that indicate using less permethrin on clothing will result in diminished performance. Follow the direction exactly and you will be amazed at the performance of this product.
Test on ticks conducted in Massachusetts concluded that 100% protection was provided against the blacklegged or "deer" tick (Ixodes scapularis) which is the primary vector of Lyme disease in the Midwest and Northeast. The same outstanding results occurred when testing the Western Black Legged tick, Lone Star tick, American Dog tick and Brown Dog tick. Similar results have been found with other tick species throughout the United States and Europe. Two detergent washings did not diminish repellent killing action of permethrin-treated clothing. In tests, ticks that crossed only 10 inches of treated fabric fell from the treated clothing, later dying due to this limited exposure.
Developed by the U.S. Army in 1946, DEET (N, N-.diethyl-m-tiluamide) is a synthetic chemical that provides one to six-plus hours of complete protection against mosquitoes, depending on its concentration. DEET has been used billions of times by hundreds of millions of people (including an estimated 30 percent of the U.S. population each year). When properly applied, it has virtually no proven adverse health effects, though in rare cases a contact skin rash can result from exposure. The EPA has completed several comprehensive assessments of DEET over the years (most recently in 1998) and concludes that repellents containing DEET do not present a health concern as long as consumers follow label directions.
DEET is an approved repellent for skin application, however exposure to high concentrations of DEET can pose some limited health hazards. DEET based products are available in a wide variety of formulas that can address the very specific needs of the individual traveler, outdoors person, family member and even young children.
Early research on DEET showed that performance dropped off when concentrations of 35% or higher were tested. As an example, if a 30% DEET concentration offers satisfactory repellent action for four hours, an assumption that a 60% DEET would last eight hours is not correct. The 60% product may only last about 5 hours. In the use of standard DEET formulas, it is more effective to use lower concentrations of DEET with more frequent application than to assume the higher concentrations to be longer lasting. They are not. Most brand-name DEET-based products already have a DEET range from 15% to 33%. Once the threat of insect/tick bite is over, the repellent should be washed off. DEET by itself tested between 85% to 89% effective at repelling ticks (DEET does not kill either ticks or mosquitoes) and 97% against mosquitoes.
Created by Bayer in the 1980's, picaridin (pronounced pih-CARE-a-den) is a synthetic compound developed from a plant extract from the genus Piper, the same plant genus that produces table pepper. Picaridin has been available since 1998 in Europe and Australia—where it is the best-selling insect repellent—but was approved for sale in the United States only in 2005. As with DEET, the EPA has concluded that the normal use of picaridin does not present a health concern.
Studies have shown picaridin to be as effective as DEET in repelling mosquitoes. Unlike DEET, however, picaridin is odorless, non-greasy, and does not dissolve plastics or other synthetics. The one possible concern with picaridin is its relative newness. Insufficient time has passed for long-term health risks (should they exist) to manifest themselves. A limited, but growing, number of repellents contain picaridin, including Cutter Advanced, Sawyer Premium, Repel Smart Spray, etc.
Do Essential Oils Repel Ticks?
The answer? Sorry, not so much. Many compounds that occur in nature provide a brief period of repellency against certain insects. There are well over 150 natural repellents while the most common are: Citronella, Eucalyptus, Lemon Leaves, Peppermint, Lavender, Cedar Oil, Canola, Rosemary, Pennyroyal, and Cajeput. Persons concerned about exposure to DEET or who prefer a natural solution can use essential oils. Generally, the EPA considers these oils safe to use in low dosage but overall their effectiveness is limited to less than 20 minutes. In addition, as ticks can't actually "smell" and instead rely on primarily on eyesight and sensors in their first two legs which can sense CO2 (which mammals constantly exhale and give off). Essential oils do not provide effective masking or disruption in the receptors and therefore are not considered to be effective against ticks.