IEM 1754 2HBr is a potent and selective antagonist of P2X3 receptors, which are ATP-gated cation channels primarily expressed in sensory neurons. It is widely used in neuroscience and pharmacology research to investigate the role of P2X3 receptors in pain transmission, nociception, visceral hypersensitivity, and conditions such as chronic pain, cough reflex, and overactive bladder. By blocking these receptors, it serves as a valuable tool for dissecting purinergic signaling pathways and evaluating potential therapeutic strategies targeting P2X3-mediated neuronal excitability. It is also employed in preclinical studies to assess efficacy, selectivity, and safety profiles for drug development.