One of our most popular formulas with those suffering from seasonal allergy symptoms, Natural D-hist is a non-drowsy, natural, fast acting product for support for discomfort caused by seasonal allergies. Natural D-hist uses carefully selected dosages of powerful natural components with mucolytic and immune supporting enhancing properties to provide optimal support for nasal and sinus passages. Conatins quercetin, stinging nettle leaf, bromelain, and n-acetyl-cysteine (NAC) to create an effective synergistic formula. Loading dose is 2 capsules three times daily for 7-10 days and then 1 or more capsules per day, or as recommended by your physician. 2 to 3 capsules can also be taken as needed for acute action.