natural bronchodilators for asthmabronchodilator drugs for asthmasalbutamol bronchodilatorsympathomimetic bronchodilatorsanticholinergic bronchodilatorantimuscarinic bronchodilatorsalbuterol bronchodilatorepinephrine bronchodilatorterbutaline bronchodilatormontelukast bronchodilatoradrenergic bronchodilatorssteroid bronchodilator