A comparison of the β1 and β2 effects of subcutaneous isoprenaline,sulbutamol and terbutaline in adult man

Summary The selectivity of salbutamol 250 and 500 µg and terbutaline 250 and 500 µg compared with isoprenaline when administered subcutaneously has been investigated in 6 human volunteers who showed consistant bronchospasm when challenged with histamine by nebulizer. Changes in heart rate, forearm blood flow, tremor and F.E. V.₁ were recorded and subjected to analysis of variance. Measurements were made at a fixed time interval after administration of active drugs or placebo and compared with pre-drug baseline recordings. The study was performed double-blind. A statistically significant difference was observed when all active drugs were compared with placebo, in the parameters of heart rate, F.E.V.₁ and tremor. However, when the active drugs were compared with each other, no statistically significant difference was observed.