preferred_name: Methacholine Chloride;Methacholine Chloride;Methacholine Chloride;Methacholine Chloride;Methacholine Chloride;Solution, Multi Ingredient 0.0625 MG/1 ML; 0.25 MG/1 ML; 1 MG/1 ML; 4 MG/1 ML; 16 MG/1 ML; NA Inhalation Solution