[Chronic Pruritus: A Review of Its Pathophysiology and Current Treatments]

Pruritus is defined as an unpleasant somatic sensation that persists for more than 6 weeks. It involves sensory, emotional, and motivational components that drive scratching. It is the most common cutaneous symptom. Its prevalence ranges from 8% to 25.5% in the European population.

Describe the current evidence-based therapeutic options for chronic pruritus, including innovative alternatives, based on a review of the pathophysiological mechanisms involved in the production of the symptom.

A Scoping Review of the literature on the pathophysiology and treatments of chronic pruritus was conducted, covering studies from March 2013 to May 2023. The review included 24 articles from MEDLINEplus and SciELO, of which 17 met the inclusion criteria and were selected for in-depth analysis. The focus was on pathophysiology, diagnosis, and therapeutic options, with the aim of improving the clinical management of chronic pruritus.

Chronic pruritus involves both histaminergic and non-histaminergic pathways, mediated by G protein-coupled receptors and transient receptor potential channels. Interleukins 4, 13, 21, and thymic stromal lymphopoietin play a crucial role, offering new therapeutic perspectives. Management should be holistic and multidisciplinary. Topical treatments are suggested for localized pruritus, while systemic therapy (antihistamines, immunosuppressants, and biologics) is recommended for generalized pruritus or localized pruritus refractory to topical treatments. Currently, various biological agents, such as dupilumab, tralokinumab, and lebrikizumab, have demonstrated efficacy in atopic dermatitis, whereas the anti-interleukin 31 monoclonal antibody, nemolizumab, shows promise as an alternative in the management of chronic pruritus.

A stepped pharmacological approach, tailored to the individual symptomatology of each patient, facilitates the treatment of chronic pruritus. Although progress has been made in understanding the pathophysiology and pharmacology associated with pruritus management, this symptom still requires further national epidemiological studies to determine its prevalence and to objectively assess its impact on the quality of life of affected individuals.