Catnip essential oil mixed into an unscented lotion at just 2% concentration repels over 70% of mosquitoes for up to four hours. That’s the simplest and most effective DIY method backed by research. The active compound in catnip, called nepetalactone, triggers an irritant receptor in mosquitoes that makes them avoid treated skin, and a 6% catnip oil lotion has performed on par with 15% DEET in field trials.
Why Catnip Works Against Mosquitoes
Nepetalactone, the oil that makes cats go wild, activates a receptor called TRPA1 in insects. This is the same receptor that detects noxious, irritating chemicals. When mosquitoes encounter nepetalactone, their nervous system reads it as a chemical threat, and they fly the other way. A 2021 study in Current Biology confirmed this mechanism in both fruit flies and Aedes aegypti mosquitoes (the species that carries dengue and Zika). Mutant mosquitoes that lacked this receptor were no longer repelled by catnip, proving it’s the specific trigger.
This irritant pathway is ancient and widely shared across insect species, which means catnip doesn’t just work on mosquitoes. Extracts from specially bred catnip cultivars repel blacklegged ticks and Asian longhorned ticks at levels comparable to DEET, maintaining effectiveness for at least eight hours in lab tests. One extract even shortened tick lifespans on contact.
The Lotion Method: Best for Home Use
Researchers have directly compared two approaches: diluting catnip essential oil in olive oil versus mixing it into an unscented hand lotion. The lotion wins decisively. A 2% catnip oil in olive oil provided significant repellency for about one hour. The same 2% concentration mixed into lotion extended protection to four hours. The lotion likely holds the oil on your skin longer instead of letting it evaporate quickly.
To make this at home, you need two things: catnip essential oil (sold online and at health food stores, look for Nepeta cataria oil with high nepetalactone content) and an unscented body lotion.
- For a 2% concentration: Add roughly 12 drops of catnip essential oil per ounce (30 mL) of unscented lotion. This gives you one to four hours of protection depending on conditions.
- For a 6% concentration: Add about 36 drops per ounce of lotion. Field trials in Uganda found this concentration matched 15% DEET against wild mosquito populations, including malaria-carrying species.
Stir or shake thoroughly until the oil is evenly distributed. Store in a small jar or squeezable tube. Apply to exposed skin as you would any lotion. The U.S. Environmental Protection Agency has reviewed catnip essential oil and deemed it safe for human use, and skin irritation testing has shown no reaction at concentrations up to 25%.
Other Methods That Work Less Well
Rubbing fresh catnip leaves directly on your skin does provide some repellency, but the effect is weaker and shorter-lived than using concentrated essential oil. Dr. Nathaniel Melo, a researcher who has studied catnip repellency in the lab, confirmed that essential oil outperforms crushed fresh leaves in both strength and duration.
You can also infuse catnip in olive oil by chopping fresh leaves and heating them in oil at around 200°F, then straining. This produces a mild repellent, but the nepetalactone concentration will be far lower than commercial essential oil. Think of it as a backup option if you grow catnip and don’t have essential oil on hand. It won’t give you the same four-hour window that the lotion method provides.
A Spray Version
If you prefer a spray over lotion, you can make one using witch hazel or rubbing alcohol as a base. Combine about 30 drops of catnip essential oil with 2 ounces of witch hazel in a small spray bottle. Shake well before each use and spray onto exposed skin. Keep in mind that liquid carriers evaporate faster than lotion, so expect to reapply more frequently, roughly every 30 to 60 minutes. Adding a small amount of vegetable glycerin (about half a teaspoon per 2 ounces) can help the mixture stick to skin a bit longer.
How It Compares to DEET
The relationship between catnip and DEET is more nuanced than early headlines suggested. In lab dish tests where both compounds are applied at identical concentrations to a surface, catnip oil performs statistically similar to DEET at deterring mosquitoes from landing. But in tests on human volunteers’ skin, pure nepetalactone compounds were significantly less effective than DEET at preventing actual bites. The key variable is formulation. When catnip oil is mixed into a lotion that keeps it on the skin, a 6% concentration matched 15% DEET in real-world field conditions with wild mosquitoes in Eastern Uganda.
The practical takeaway: catnip can rival DEET, but only when the formulation keeps the oil in contact with your skin. A lotion base does this. A quick rub of fresh leaves does not.
Reapplication and Storage Tips
Plan to reapply your catnip lotion every two to four hours, depending on how much you’re sweating and the mosquito pressure in your area. For the spray version, reapply every 30 to 60 minutes. Heavy sweating, swimming, or toweling off will remove the repellent faster.
Catnip essential oil degrades with exposure to light and heat. Store your premixed lotion in an opaque container at room temperature or in the refrigerator. A batch should stay potent for several weeks. If it starts to smell more like dried grass than sharp mint, the nepetalactone has likely broken down and it’s time to make a fresh batch.
One bonus: because nepetalactone activates a broadly shared irritant receptor across insects, your catnip repellent may also help deter gnats, flies, and ticks, though mosquitoes remain the best-studied target.