Beyond sodium channel blockade: Flavonoid as alternative local anesthetic candidates of lidocaine.

When conventional drug-based Western medicine proves ineffective, complementary and alternative medicine (CAM), including herbal medicine and acupuncture, often gains prominence. Phytochemicals, plant-derived compounds synthesized for self-protection against environmental stressors like ultraviolet radiation and insects, have also shown numerous physiological benefits in humans. Among these, flavonoid compounds - abundant in fruits and vegetables - have garnered significant research interest due to their reported biological activities, such as antioxidant, anti-inflammatory, and anticancer effects. Recent in vitro studies have provided substantial evidence that flavonoids modulate the activity of various ion channels. These channels are crucial for the generation and conduction of activation and action potentials in excitable cells, including those involved in pain transmission. These findings strongly suggest that flavonoids could serve as novel therapeutic agents for pain relief, potentially replacing existing local anesthetics. This paper discusses recent in vivo neurophysiological findings which reveal the potential of flavonoids to substitute existing local anesthetics in nociceptive and inflammatory pain. We explore the possibility of developing new drugs with fewer side effects by focusing on the common chemical structure of flavonoids, addressing the shortcomings of current anesthetics, and outlining future prospects.