Levocloperastine in the treatment of chronic nonproductive cough: comparative efficacy versus standard antitussive agents.
The medical and social impact of cough is substantial. Current antitussive agents at effective doses have adverse events such as drowsiness, nausea and constipation that limit their use. There is also recent evidence that standard antitussive agents, such as codeine, may not reduce cough during upper respiratory infections. Therefore, there is a need for more effective and better-tolerated agents. The efficacy of levocloperastine, a novel antitussive, which acts both centrally on the cough center and on peripheral receptors in the tracheobronchial tree in treating chronic cough, was compared with that of other standard antitussive agents (codeine, levodropropizine and DL-cloperastine) in six open clinical trials. The studies enrolled patients of all ages with cough associated with various respiratory disorders including bronchitis, asthma, pneumonia and chronic obstructive pulmonary disease. Levocloperastine significantly improved cough symptoms (intensity and frequency of cough) in all trials, and improvements were observed after the first day of treatment. In children, levocloperastine reduced nighttime awakenings and irritability, and in adults it was effective in treating cough induced by angiotensin-converting enzyme inhibitors. When compared with other antitussive agents, levocloperastine had improved or comparable efficacy, with a more rapid onset of action. Importantly, no evidence of central adverse events was recorded with levocloperastine, whereas drowsiness was reported by a significant number of patients receiving codeine. Levocloperastine is an effective antitussive agent for the treatment of cough in patients of all ages. It has a more rapid onset of action than standard agents with an improved tolerability profile.