Impermeable bed covers don't help allergic rhinitis

Question Do impermeable bed and pillow covers improve symptoms of allergic rhinitis?

Synopsis Impermeable bed and pillow covers reduce the exposure of allergic patients to dust mite allergens–but is that enough to improve symptoms? Previous studies have been small and poorly designed and have provided conflicting results. In this randomised controlled (double blinded) trial, adults and children aged 8 to 50 years who were allergic to dust mites were randomised (allocation concealed) to receive …