A placebo-controlled evaluation of butterbur and fexofenadine on objective and subjective outcomes in perennial allergic rhinitis

Summary Background There are presently no placebo‐controlled data regarding the effects of butterbur (BB) on subjective and objective outcomes in patients with perennial allergic rhinitis. Objective We performed a placebo‐controlled evaluation of the effects of BB and fexofenadine (FEX) on subjective and objective outcomes in patients with perennial allergic rhinitis. Methods Sixteen patients with perennial allergic rhinitis and house dust mite sensitization were randomized in double‐blind cross‐over fashion to receive for 1 week either BB 50 mg twice daily, FEX 180 mg once daily and placebo (PL) once daily, or PL twice daily. The peak nasal inspiratory flow (PNIF) response to adenosine monophosphate (AMP) challenge administered as a single 400 mg/mL dose was measured over a 60‐min period after challenge, and domiciliary total nasal symptom score was recorded. Results Pre‐challenge values for mean±SEM PNIF (L/min) were not significantly different comparing all groups; BB (138±8), FEX (140±9), and PL (138±8). The maximum % PNIF fall from baseline after nasal AMP challenge was significantly attenuated (P