This is the second purifierHEPA filter that Ive bought.  I have bad Michigan allergies, as well as an allergy to pet dander.  I love animals, and am currently a foster for kittens and have a special needs St. Bernard as well, so have been living on allergy meds and nasal sprays.  Sleep was difficult as well - but to help these babies, you do what you have to.  Since getting the purifiers (first is in the living roomkitchen area the second is in my bedroombath area.) Im not having the issues I normally have and am sleeping better.  What a difference they have made!  Wish Id bought them sooner!