What's the best medicine for allergies?

Lots of Options: Over-the-counter non-sedating antihistamines like Allegra, Claritin, or Zyrtec are helpful for perennial allergic rhinitis symptoms, however the gold-standard treatment are daily intranasal steroid sprays like Flonase or Nasonex (mometasone) if your symptoms are more severe. Avoidance of triggers is important. Allergy shots also option. See Allergist to determine what medications could give you lasting relief.