What is the Best Insect Repellent?

Mosquito sitting on green leaf

Why You Need to Consider Your Insect Repellent Carefully

Insects and humans have a history as intertwined as fabric weaving together the strands of the silkworm. Few creatures on Earth have inspired such reverence and hatred at the same time. They embody the transformative power of nature on a scale and magnitude unthinkable to mammals like ourselves. The duality of creation and destruction at the core of insect kind is exemplified by the cochineal bug parasitic to cacti and yet from whose body the most gorgeous red pigment has been extracted for centuries. 

While we often take for granted the services rendered by insects, we rightly fear their power as disease vectors. This fear extends back millenia; three of the ten plagues of Egypt were bugs: flies, lice, and locusts. Despite the advances of modern medicine, insect-borne diseases continue to plague humanity, including in Western nations. In fact, many bothersome and potentially dangerous insects thrive in the United States, most notably the mosquito and the tick (though ticks are technically arachnids). 

This article will consider the most common bugs that pose a threat to human well-being, from lethal disease to bothersome bites. Specifically, it will cover insect repellant, one of the most effective ways to prevent insect-related harm. Included are the different proven active ingredients, approval and vetting of products, and best practices for safely applying and reapplying insect repellent. 

Ultimately, we’re all trying to live our lives and let others live theirs. Insect repellent can accomplish us by diverting bugs away from ourselves and our families and back toward their important ecological tasks. Read on for the information to make it happen. 

Consider the Type of Insect You Need Protection from

The first step in protecting yourself from insects is identifying which type(s) you need protection from. Given that different products are geared toward repelling certain insects, getting this question right will greatly impact efficacy.

Geography Matters

The answer will have lots to do with ecology–the biome will largely determine the types of flora and fauna that exist therein. For example, mosquitos and many other bugs require water to reproduce and thus are more prevalent in moist environments. In the Boundary Waters of Northern Minnesota, residents joke that their state bird is the mosquito in reference to the size and quantity of the population enabled by the plentiful lakes and swamps. However, the deep winters and temperate climate can decrease the spread of infectious disease. 

Ticks & Mosquitoes

The main bugs you need to know are ticks and mosquitoes. Within the tick family, different species like Deer Ticks, Wood Ticks, and Lone Star Ticks all live in different geographical zones and transmit specific diseases. Among these, Lyme disease is the most common and can result in potential lifelong symptoms. Anaplasmosis and Rocky Mountain Spotted Fever are other more common tick-borne diseases. Consider the range of tick species in your area as well as the prevalence of tick-associated diseases to assess your specific risk.

Mosquitoes are common around the world and the United States and are the leading disease vector among insects. Leading mosquito-borne illnesses include West Nile Virus and different types of Encephalitis. More often than not, however, they constitute an extreme annoyance. Mosquitoes thrive in the more humid climate of the southern U.S. and at northern latitudes during the warm months. Their populations decrease west of the Rocky Mountains but certain areas in Western states will see sizable populations as well. 

Consult reputable sources to assess the specific insects you wish to repel.

Look for EPA-approved products

The United States Environmental Protection Agency (EPA) routinely evaluates the ingredients and effectiveness of many insect repellants. In these evaluations, the EPA will specify 1) the hourly duration of protection time for both mosquitoes and ticks, 2) the active ingredient in the formula, and 3) the active ingredient percentage of the total formula. 

In 2014, the EPA began allowing companies to use repellency awareness graphics on their products which display the type of insect repelled and the duration of protection. These graphics, which appear in yellow and black on the front of certain products, connotes that the EPA has reviewed the scientific evidence for the products’ effectiveness. Products without EPA registration have been tested for safety but the EPA has not made a determination about their effectiveness. Products that use ingredients like citronella and cedar often fall into this category. In these cases, consumers would need to do their own research given the lack of evaluation and oversight from any government agency. 

Choose a repellent with an active ingredient that is proven to be effective

Wandering through the ether of product marketing presents a wearisome array of embellished or simple untrue claims. An untold number of Americans sought out an unproven and potentially harmful horse dewormer for the treatment of COVID-19 and two even died from consuming fish tank cleaner for the same purpose. Undoubtedly, structural problems exist in the research industry that serve to promote certain products and dismiss others. However, peer-reviewed studies that use scientific methods are one of the best sources for true and verifiable knowledge. In the case of insect repellant, scientists have conducted hundreds of studies to evaluate specific ingredients, the results of which have been reviewed and disseminated by organizations like the EPA. Importantly, the safety of these products has also been tested and verified. 

Common ingredients proven to be effective include:

  • DEET: N,N-Diethyl-meta-toluamide, also known as DEET, is the most common active ingredient in insect repellants. It was developed during WWII to protect U.S. soldiers and has since been used and tested widely. While it has the possibility to irritate skin, very few studies have indicated any toxic effects, and those that have occurred with extensive, long-term use.
  • Picaridin: Reported to be as effective as DEET, picaridin (or icaridin) with less potential for irritation. At concentrations of 20%, it can repel ticks for up to 12 hours. In general, picaridin presents significant repellent qualities with little risk, despite enjoying less use than DEET. 
  • Lemon eucalyptus oil: the oil lemon-scented gum tree of northeastern Australia can be extracted and processed into an effective insect repellent. It smells very similar to citronella and provides a naturally-derived option for insect repellent with similar effectiveness to DEET, though it can have a shortened length of protection

Consider the length of protection

Even if one correctly determines problem insects in their area, chooses the right repellant and applies it correctly, they would still enjoy protection for a limited amount of time, after which they would once again be vulnerable. Considering the ingredients above, certain products are better fitted to specific uses. Additionally, the concentration of the active ingredient can make a difference in the length of protection offered. Products should themselves indicate this time period, but the EPA also details this information for registered products. 

Long hikes, for example, would require either a) long-lasting repellent, or b) reapplication of products with shorter periods of protection. Extended periods of outdoor activity require a conscientious approach to insect protection, especially given the waxing and waning of insect activity over the day. For instance, dusk is a time when mosquitoes tend to swarm, so anticipating this period with thoughtful repellent application provides the best protection. 

Take precautions when applying insect repellent

While the EPA evaluates the safety of many products, this only applies when products are applied properly. Insect repellents are meant only for external use, meaning users need to avoid getting the product in mucus membranes like eyes, mouth, etc. Additionally, given some ingredients’ ability to irritate the skin, users should avoid applying repellent to cuts, wounds, and irritated skin, as this could increase irritation. 

Children require special consideration since they often have less ability to consider the potential for irritation. It is best to avoid applying repellent to children’s hands, as they may transfer the repellant to their eyes or mouths by accident. Products will always provide written instruction for proper use; deviating from these practices carries risk. 


Nothing can so easily ruin a gorgeous moment outside as a swarm of insects. While we humans like to think of ourselves as apex predators, insects humble us in their ability to feed on our bodies. Even in the most highly industrialized nations, insect populations continue to thrive, causing countless itchy bites and spreading serious infectious diseases. In response, humans have taken a page out of some prey animals’ playbook and developed compounds to deter predators and parasites. Insect repellents can provide safe and easy ways to avoid bug bites and the problems they cause.

Still, a lot goes into effective insect protection. Consumers will need to know the bugs and insects they seek to repel, match these to the effective active ingredients in a repellent, and choose a proven product. Finally, correct application will make the difference between comfort and risk. Check out the rest of the Pure Pest website to learn more about effective ways to control problematic insects.