Pathogenesis of Vitiligo (Switra) – An Ayurvedic Understanding

Abstract

Switra, described in Ayurveda, is a skin disorder characterized by depigmented patches, which can be correlated with vitiligo in modern medicine. This condition results from the loss of melanocytes and is influenced by factors such as improper diet, genetic predisposition, stress, and environmental triggers. Ayurveda explains the pathogenesis of Switra as a derangement of the body’s doshas, particularly Pitta, which affects metabolism and complexion. The disease can be categorized into three types based on severity, and deeper involvement of tissues indicates a poor prognosis. Modern scientific research suggests that vitiligo arises from multifactorial causes, including autoimmune mechanisms, oxidative stress, neural factors, genetic predisposition, and environmental triggers. The autoimmune hypothesis, which involves the destruction of melanocytes by T-cell-mediated cytotoxicity, is the most widely accepted. Additional theories suggest oxidative damage, neural disruptions, and inflammatory processes contribute to the disease. In Ayurveda, Switra's pathogenesis involves the accumulation of Ama due to deranged Jatharagni and the vitiation of Tridosha (Vata, Pitta, Kapha), which disrupts skin pigmentation. The role of Bhrajaka Pitta, responsible for skin color, is diminished in vitiligo, and the imbalance in Vata and Kapha exacerbates melanocyte damage. The interplay of genetic factors, autoimmune responses, oxidative stress, and doshic imbalances leads to the characteristic depigmented lesions observed in vitiligo. Understanding these mechanisms can aid in developing more effective treatment and prevention strategies.