Accidental exposure of honey bees to agricultural insecticides often results in bee death, yet many pest insects can survive insecticide exposure because they are able to quickly metabolize and detoxify insecticides. I found that bees have a very limited ability to detoxify cyfluthrin, a pyrethroid insecticide, using cytochrome P450 monooxygenase enzymes found in the midgut. Increased expression of these P450s could render bees more resistant to pyrethroid insecticides. In many animals detoxicative P450 expression can be induced by limited contact with the toxin or another inducing compound. Previous research has shown that Apistan, which contains the pyrethroid tau-fluvalinate, can induce P450s involved in benzo(a)pyrene metabolism in honey bees. To look for induction of pyrethroid-metabolizing P450s, I compared the rate of cyfluthrin detoxification in bees of different ages taken from colonies treated with Apistan and bees from untreated colonies.