Fexofenadine is associated with a lower risk of cardiac arrhythmia compared to terfenadine.
Please see package insert for additional information and possible updates.
E-triprolidine, for example, is 1000-fold more potent than Z-triprolidine.
This lack of receptor selectivity is the basis of the poor tolerability profile of some of these agents, especially when compared with the second-generation HDiphenhydramine was the prototypical agent in this group.
Mechanism of Action Desloratadine is a long-acting tricyclic histamine antagonist with selective H1-receptor histamine antagonist activity.
Receptor binding data indicate that at a concentration of 2–3 ng/m L (7 nanomolar), desloratadine shows significant interaction with the human histamine H1-receptor.
Once released, the histamine can react with local or widespread tissues through histamine receptors.
Histamine, acting on H-antihistamines help against these effects, they work only if taken before contact with the allergen.