Pollen Allergy

I have a pollen allergy.
I had been expecting that I wouldn't have it in the United States.
Unfortunately, I have suffered from it since last Wednesday.
An allergen which causes an allergy would be "BUTAKUSA" in Japanese.
I don't know the English name.
I have brought some herbal medicine from Japan, but I heard I could buy medicine for an allergy without a prescription here. They are what a doctor prescribes in Japan.
I should go to a drug store because I cannot concentrate on anything.
Though I don't like overprescription!