Beneficial health applications and medicinal values of Pedicularis plants: A review

Pedicularis plants (Orobanchaceae), popularly known as lousewort, are found in Asia, Europe, and North America, and have been used in Sowa-Rigpa, the Himalayan art of healing and a traditional system of medicine for treating various ailments in humans. A comprehensive compilation on this valuable medicinal plant is not available, however. The present extensive review provides insight into the salient medicinal properties of Pedicularis plants with respect to various health issues and diseases. Our previous studies on Pedicularis plants from the Changthang region of Ladakh (India) and research advances leading to new developments in this field have prompted this review. The information presented here has been compiled and analyzed from authenticated published resources available on Medline, Pubmed, Pubmed Central, Science Direct, and other scientific databases. The Pedicularis genus consists of approximately 600 species (83 of which are found in India), with commonly reported species being Pedicularis longiflora Rudolph, P. bicornuta Klotzsch, P. oederi Vahl, P. cheilanthifolia, and P. pectinata. The major phytoconstituents of the Pedicularis sp. are phenols, phenylethanoids, phenylpropanoids, flavonoids, iridoids, lignans, and alkaloids, among others. The existing literature highlights that these compounds possess antioxidant, immunomodulatory, anti-inflammatory, antidiabetic, antibacterial, antifungal, analgesic, antitumor, hepatoprotective, neuroprotective, muscle-relaxing, antifatigue, diuretic, antipyretic, antithrombus, antihemolysis, and DNA-repairing properties. This medicinal herb is used in the treatment of leucorrhoea, fevers, sterility, rheumatism, general debility, collapse, and urinary problems, and for revitalizing the blood circulation, improving digestion, and maintaining vitality. This review emphasizes the various medicinal aspects of Pedicularis sp. plants containing a variety of phytoconstituents. Besides phenols, terpenoids, flavonoids, lignans, tannins, iridoid, and phenylpropanoid glycosides are among the active constituents responsible for multiple health effects. However, further extensive research is required to characterize the various phytoconstituents of Pedicularis to explore their modes of action at a molecular level and identify other beneficial applications that can exploit the tremendous medicinal potential of this important herb.