Effect of single doses of inhaled lignocaine on FEV1 and bronchial reactivity in asthma.

Inhaled lignocaine appeared to have considerable steroid sparing properties in an uncontrolled trial in 20 patients with oral-steroid-dependent asthma. Since it can also cause bronchoconstriction, safety needs to be studied under controlled conditions. We have performed a randomized, double-blind, placebo-controlled study in 20 patients with mild to moderate asthma to determine the effects of single doses of inhaled lignocaine 40 and 160 mg compared to saline. Saline and lignocaine 40 and 160 mg caused an initial fall in FEV1, mean maximum change being 0.13, 0.19 and 0.231 respectively with no significant difference between treatments (P = 0.2). There was no fall in FEV1 following salbutamol pretreatment and lignocaine had no significant effect on heart rate or blood pressure or on bronchial reactivity to methacholine carried out at 90 min after inhalation. These results show that single doses of inhaled lignocaine are well tolerated in subjects with mild to moderate asthma and that any tendency to bronchoconstriction can be prevented with salbutamol pretreatment.