Research Area: Neurological Disease Biological Activity: Lidocaine (Alphacaine)is a selective inverse peripheral histamine H1-receptor agonist with an IC50 of >32 μM. [1] Histamine is responsible for many features of allergic reactions. Lidocaine (Alphacaine)is a second-generation antihistamine agent closely structurally related to tricyclic antidepressants such as imipramine, and distantly related to the atypical antipsychotic quetiapine, used to treat allergies. [2]