Alverine citrate decreases airway contraction to multiple stimuli and in 2 species. A: alverine (ALV; 15 or 2 mg/kg) or vehicle control (Veh) was administered intraperitoneally, 30 min before airway-resistance (R) measurements. Alverine citrate was also nebulized (neb; 15 mg/ml). Data are means ± SE; Veh, n = 4 mice; ALV (15 mg/kg ip), n = 4 mice; ALV (2 mg/kg ip), n = 3 mice; nebulized ALV, n = 3 mice. B: murine lung slices were incubated with 20 μM alverine citrate or vehicle control and stimulated to contract by perfusion with distilled water for 1 min (marked line, H2O). Data are means ± SE of lumen area as a percent of basal area. Veh, n = 9; ALV, n = 8. C: porcine lung slices were incubated with 20 μM alverine citrate or vehicle control and then stimulated to contract by perfusion with increasing concentrations of substance P (Sub P; 1, 10, and 100 μM). Veh, n = 5; ALV, n = 5. D: porcine lung slices were incubated with 20 μM alverine citrate or vehicle control and then stimulated to contract by perfusion with increasing concentrations of methacholine (MCh; 1, 10, and 100 μM). Veh, n = 4; ALV, n = 5. E: porcine lung slices were perfused with 20 μM alverine citrate or vehicle control during the time indicated. No agents were administered to stimulate contraction. Veh, n = 5; ALV, n = 5. F: alverine (15 mg/kg) or vehicle control was given intraperitoneally to nonsensitized acid-sensing ion channel (ASIC)1a−/− mice, 30 min before measurement of airway resistance at increasing doses of methacholine. Veh, n = 3; ALV, n = 3. For all panels, *P < 0.05 for treatment in 2-way ANOVA.