Adenosine monophosphate (AMP) is an inflammatory mediator that serves as an indirect bronchial stimulus for detecting airway hyperresponsiveness in asthma. Compared with histamine, AMP may be pathophysiologically more relevant to airway inflammation and hyperresponsiveness and has been linked to presence and magnitude of atopy. However, differences of response to AMP-BPT and His-BPT in different asthma control levels and their associations with asthmatic symptom scores have not been fully elucidated.