Celer Syrup is an antihistamine medication formulated with desloratadine, a non-sedating H1 histamine receptor antagonist that effectively relieves symptoms of allergic conditions such as allergic rhinitis and chronic idiopathic urticaria (hives) by blocking the action of histamine, a substance responsible for allergic reactions. It helps alleviate sneezing, runny or itchy nose, itchy palate, red or watery eyes, and skin rashes or hives with itching.