Picaridin, sometimes called icaridin, is a synthetic chemical designed to mimic a naturally-occurring chemical called piperidine, which is found in the species of plants that includes common black pepper. It was developed by Bayer in the 1980s. It came into use as a bug spray in Europe and Australia in 1998 but wasn’t approved for use in the United States until 2005. Today, it serves as an alternative to DEET bug spray. While the two chemicals have been shown to have similar efficacy, picaridin bug spray is sometimes thought to feel less greasy on the skin than DEET products. Unlike DEET bug spray, picaridin-only products won’t damage plastics or other synthetic materials. While DEET is more well-established and considered the best possible mosquito protection by the World Health Organization, picaridin products have gained popularity in recent years and are now the best-selling mosquito repellants in Europe and Australia. In the United States, picaridin-based mosquito repellants have gained more of a market share with widely-available brands like Cutter Advanced, Sawyer Premium, OFF!, and Repel Smart Spray offering picaridin-based repellants.