The effect of inhaled lidocaine–hydrofluoroalkane 134a in prednisone-dependent eosinophilic bronchitis

To the Editors: We report on the preliminary findings with inhaled lidocaine in patients with eosinophilic airway inflammation, identified by sputum cell counts (eosinophilic bronchitis), with or without asthma, who are prednisone dependent. Lidocaine has been shown to possess anti-eosinophil 1, 2 and anti-spasmodic 1, 3 actions, as well as steroid-sparing efficacy 4, 5. However, the anti-eosinophil effects have not been demonstrated in humans in vivo. Furthermore, the delivery of lidocaine by nebulisation, as utilised in previous clinical studies 4, 5, makes the treatment inconvenient. Therefore, we synthesised a preparation of lidocaine in a hydrofluoroalkane (HFA)134a, pressurised metered-dose inhaler (MDI) and investigated the prednisone-sparing and anti-eosinophilic effects. Five patients requiring daily prednisone in addition to high-dose inhaled corticosteroid to treat eosinophilic bronchitis (fig. 1⇓) were randomised in a double-dummy, crossover study to add-on lidocaine or HFA134a MDI placebo. After 4 weeks, the prednisone dose was reduced monthly by 5 mg until either a loss in symptom control or the prednisone dose was discontinued for 1 month. All subjects had been unable to reduce …