Correlations between theophylline concentrations in plasma,erythrocytes and cantharides-induced blister fluid and peak expiratory flow in asthma patients

Summary Theophylline levels in plasma, erythrocytes and cantharides-induced blister fluid (BF) have been correlated with peak expiratory flow (PEF) in asthmatic patients. Nine asthmatic men received an IV infusion of 240 mg theophylline at a constant rate for 30 min.The theophylline concentrations in erythrocytes and blister fluid were 37 % and 78 % of those in plasma. There was not a strong correlation between erythrocyte or blister fluid penetration and the clinical effect of theophylline.