N, N-diethyl-m-toluamide or Deet remains the gold standard of insect repellents. This substance was discovered and developed by scientists at the U.S Department of Agriculture and was patented by the U.S Army in 1946.
It is a broad spectrum repellent against mosquitoes, biting flies, fleas and ticks and despite years of testing other formulations, nothing else has been proven to provide longer protection than Deet.
It is reported that over 200,000,000 people use Deet annually around the world. As a general rule, the higher the concentration of Deet the longer lasting the protection. Extra Strength Insect Repellent will provide protection in normal conditions, for around 6-8 hours after application. Extra Strength Insect Repellent is also approved by the HSE.