Effects of single or combined mediator antagonism on nasal adenosine monophosphate challenge in perennial allergic rhinitis

We evaluated the effects of usual clinically recommended doses of fexofenadine (FEX), montelukast (ML), and FEX+ML combination, compared to placebo (PL), on nasal adenosine monophosphate (AMP) challenge in patients with perennial allergic rhinitis (PAR). 12 PAR patients were randomized in a double-blind, crossover fashion to receive for 1 week, either FEX 180 mg, ML 10 mg, FEX 180 mg + ML 10 mg combination, or PL, with nasal AMP challenge performed 12 hours after dosing. The primary outcome was measurement of peak nasal inspiratory flow (PNIF) made over a 60-minute period after nasal challenge with a single 400 mg/ml dose of AMP. Domiciliary total nasal symptoms were measured as a secondary outcome. There was significant attenuation ( p