Controversy exists regarding the safety of intravenous dipyridamole in patients with severe chronic obstructive pulmonary disease (COPD), and it is contraindicated in patients with asthma. There is currently little published literature on the safety of adenosine in patients with airways disease, despite potential advantages over dipyridamole with respect to side effects. We studied 46 consecutive patients with a history of COPD or asthma undergoing adenosine stress myocardial perfusion scintigraphy. Spirometry with measurement of forced expiratory volume in 1 s (FEV(1)), forced vital capacity, peak expiratory flow rate and a repeat FEV(1) postinhaled bronchodilator in all those with a history of asthma was performed prior to receiving intravenous adenosine 140 mg/kg/min for 4 min. The cohort exhibited significant airflow limitation on spirometry (see Table 1), however the majority of patients (24/46) did not experience any dyspnoea or chest pain during adenosine infusion. Fourteen patients experienced chest discomfort during adenosine, and 9 complained of dyspnoea. No patient required aminophylline or resuscitative measures. In our cohort of patients with a history of COPD, asthma or both who demonstrated impaired lung function on spirometry, adenosine was safe and well tolerated.