I Had no idea plugin air freshner's could cause such a major allergic reaction as I have been using these for some time till I refilled mine with double pack of air wick I have been hospitalised due to the adverse reaction which I did not know at first and hospital could not figure out what could have caused such a major allergic reaction but when I reached home after being discharged 3 days later from hospital, the itching and blotches started to appear on my skin within an hour. I have always used the plugins on the bottom plugs of an extension so as to keep away from direct exposure at any time