Carbocysteine: clinical experience and new perspectives in the treatment of chronic inflammatory diseases

Background: Carbocysteine is a muco-active drug with free radical scavenging and anti-inflammatory properties. It is actually approved for clinical use as adjunctive therapy of respiratory tract disorders characterized by excessive, viscous mucus, including chronic obstructive airways disease (COPD). Objective: The intriguing antioxidant and anti-inflammatory properties of carbocysteine, beyond its known mucolytic activity, are described to explain its therapeutic efficacy and suggest new clinical uses. Methods: After reviewing physiology and preclinical studies, human studies on the use of carbocysteine in chronic inflammatory diseases, i.e., COPD and cancer cachexia, are reviewed. Results/conclusions: Carbocysteine has been recently recognized as an effective and safe treatment for the long-term management of COPD, able to reduce the incidence of exacerbations and improve patient quality of life. Moreover, carbocysteine was effective in counteracting some symptoms associated with cancer cachexia. Preclinical and clinical studies have demonstrated that the antioxidant and anti-inflammatory properties of carbocysteine are more important than mucolysis itself for its therapeutic efficacy. Therefore, carbocysteine may be able to reverse the oxidative stress associated with several chronic inflammatory diseases, such as cardiovascular diseases and neurodegenerative disorders. Controlled, randomized studies in humans are warranted.