If you have tree allergies, Cedarcide probably caused a mild reaction.  I used the cedar oil formula (Best Yet) with a fogging machine yesterday, & have hives all over today - but I'm also very allergic to trees.  My asthma is not having the harsh reaction I expected (although that's probably attributable to maintenance inhalers - but nonetheless, it didn't kill me!)  The smell dissipates quite quickly, but you don't want to be in or around it (after fogging) for at least 24 hours.  Asthmatics & allergy sufferers should be especially careful - at least wait one day before re-entering you home.  ALSO - if possible, have a friend or family member perform the actual fogging itself if you're asthmatic!  It doesn't appear to bother normal lungs at all, yet my severely asthmatic lungs felt full of "something awful" after completing the fog.  It went away in about 24 hours, but still not something to mess around with if you have breathing probs...