I've had several people ask me recently how they can add Catnip essential oil (EO) to a bug repellent to make it more effective since they learned “catnip essential oil is ten times more effective than DEET.”
Apparently this information comes from this article by Science Daily. Here is the quote…
Peterson says nepetalactone is about 10 times more effective than DEET because it takes about one-tenth as much nepetalactone as DEET to have the same effect. Most commercial insect repellents contain about 5 percent to 25 percent DEET. Presumably, much less catnip oil would be needed in a formulation to have the same level of repellency as a DEET-based repellent.
Nepetalactone is found in Catnip (at around 50%). According to the article, the constituent nepetalactone killed 40-45% of mosquitoes tested, where the results for Catnip EO ranged from as low as 39% and as high at 59%. DEET only repelled 10% of the mosquitoes tested.
If you look at the numbers, Nepatalactone is only 50% (on average) effective. You can use Catnip as a repellent if you wish – but be forewarned – it's stinky! And not guaranteed to be 100% effective.
I recommend sticking to known effective and more pleasant-smelling insect repellents like Lemon Eucalyptus and Citronella. You can find my very best recipe here: Tick Off! Bug Off!