CP 99994 dihydrochloride have shown the compound to be a potent, selective and competitive NK-1 receptor antagonist. In preclinical studies, CP 99994 decreased cough number, peak abdominal activity, and peak tracheal pressure, without affecting baseline respiration. But in clinical trial administration of CP 99994 over 2 h does not significantly inhibit hypertonic saline-induced bronchoconstriction or cough in subjects with mild asthma. CP 99994 significantly suppressed acute postoperative pain at 90 min after surgery.