Loratadine (Claritin) is an antihistamine used to treat seasonal allergies. It works by blocking the action of histamine which causes allergic symptoms. Brand name loratadine is called Claritin, also available over the counter. Get Loratadine for as low as $2.00, which is 84% off the average retail price of $12.28 for the most common version, by using a GoodRx coupon.