Some of the best over-the-counter allergy medications are Claritin, Sudafed, and Afrin nasal spray. They are either antihistamines or decongestants that relieve allergy symptoms effectively, as reported by Women's Health.
The active ingredient in Claritin is loratadine, which is an antihistamine. It prevents allergens from binding with the receptors in the nose by blocking them. It can take up to 60 minutes for Claritin to take effect, says Women's Health.
Both Sudafed and Afrin contain decongestants, advises Women's Health. Decongestants shrink the tissues and blood vessels in the nose and eyes that have swollen due to allergens, according to WebMD. The Sudafed formula that contains pseudoephedrine is more effective than medications that contain phenylephrine, notes Women's Health.