Hi,
I did a job for a friend of my mums. She looks after dogs when people are away. Her 15 year old grandson had terrible asthmatic symptoms: sneezing wheezing etc etc, when he visited her. I cleaned her whole house and furniture, and the next time her grandson came over to visit he didnt get any of his usual symptoms.
She told me this even though I handnt told her that the pre spray I used had promite in it. It proves it works, but I believe that any pre spray and stream extraction helps with allergic symptoms.
GL
Ben