What is Claritin?
Loratadine (INN) is a second-generation H1 histamine antagonist drug used to treat allergies. In structure, it is closely related to tricyclic antidepressants, such as imipramine, and is distantly related to the atypical antipsychotic quetiapine.
Loratadine is marketed by Schering-Plough under several trade names (e.g., Claritin) and also by Shionogi in Japan. It is available as a generic drug and is marketed for its nonsedating properties. In a version named Claritin-D or Clarinase, it is combined with pseudoephedrine, a decongestant; this makes it useful for colds, as well as allergies but adds potential side effects of insomnia, anxiety, and nervousness.