ClenbuterolAlbuterolAdrenergic beta-AgonistsDrug ResiduesAdrenergic beta-2 Receptor AgonistsBronchodilator AgentsNebulizers and VaporizersEthanolaminesFenoterolAdministration, InhalationReceptors, Adrenergic, beta-2IpratropiumAtropine DerivativesAsthmaAdrenergic beta-2 Receptor AntagonistsMetered Dose InhalersForced Expiratory VolumePeak Expiratory Flow RateAerosolsAminophyllineMetaproterenolAdrenergic beta-AntagonistsDouble-Blind MethodReceptors, Adrenergic, betaPowdersCross-Over StudiesDoping in SportsTerbutalineInhalation SpacersIsoproterenolAmino AlcoholsAirway ResistanceBronchoconstriction