Novel HS-Releasing Bifunctional Antihistamine Molecules with Improved Antipruritic and Reduced Sedative Actions.

Hydrogen sulfide (HS) is an endogenous gasotransmitter with anti-inflammatory actions that also reduces itching. To test whether a combination of an antihistamine with a HS donor has improved antipruritic efficacy, bifunctional molecules with antihistamine and HS-releasing pharmacophores were synthesized and tested and . HS release from the hybrid molecules was evaluated with the methylene blue and lead acetate methods, and H1-blocking activity was assessed by determining tissue factor expression inhibition.