Efficacy and tolerability of levodropropizine and clobutinol in elderly patients with nonproductive cough

In a double-blind, randomised, clinical trial involving 191 elderly patients of either gender affected by nonproductive cough, the therapeutic efficacy and tolerability of oral levodropropizine and clobutinol (60 mg three times daily for 3 days, for both agents) were evaluated. Efficacy was assessed by analysing cough intensity, the number of coughing spells in the 5 hours post-treatment, and night awakenings due to cough; tolerability was evaluated by analysing laboratory data, vital signs, dyspnoea and any adverse event occurring during the clinical trial, including the presence or absence of somnolence. Independent of the underlying pathology, cough intensity was significantly (p <0.01) reduced by both drugs at the end of the treatment period; moreover, the number of coughing spells was significantly (p <0.01) reduced by both drugs after the first day of treatment. In addition to the relief of cough, the number of night awakenings was significantly decreased (p <0.01) by both treatments. No changes in laboratory data were considered clinically relevant; vital signs were not clinically affected by either study drug. Mild somnolence was reported for a low percentage of patients (<15%) with both drugs; the percentage of patients experiencing this adverse effect was about 50% lower with levodropropizine (6.5%) than with clobutinol (14.6%), although this difference was not statistically significant. Dyspnoea also improved throughout the treatment period. These data indicate that both levodropropizine and clobutinol have antitussive efficacy and are free of bronchopulmonary adverse effects in elderly patients, although a central effect such as somnolence was experienced with a certain frequency, especially with clobutinol.