I was wondering what are the differences between loratadine and desloratidine?

Des/loratadine: Desloratadine is the primary metabolite is loratadine. The advantage is thought to be quicker onset of action and longer action of anti-histamine effect. There is a small percentage of patients in which neither drug is able to be metabolized adequately. At usual doses, both are considered non-sedating specific h1 antagonists. Clinically speaking both are useful drugs for typical allergies.