Nanomedicine for chronic pain management: From pathophysiology to engineered drug delivery systems

Chronic pain represents a significant burden on individuals and society, impacting financial costs, emotional well-being, and productivity. Traditional treatments for chronic pain, such as non-steroidal anti-inflammatory drugs (NSAIDs), opioids, and local anesthetics, are commonly used but have notable limitations. Opioids carry a risk of addiction, NSAIDs pose gastrointestinal and cardiovascular risks, and the short duration of analgesic effects from single doses of local anesthetics limits their effectiveness in long-term pain management. This review aims to provide a comprehensive resource for researchers exploring innovative approaches to chronic pain treatment, with a particular focus on drug delivery systems. It delves into the classification of chronic pain, its underlying mechanisms, and the most commonly used pharmacological treatments, while critically evaluating the limitations of each strategy. Furthermore, the review highlights recent advancements in drug delivery technologies for chronic pain management, discussing both the potential opportunities and challenges of translating these innovations into clinical practice. Ultimately, the review identifies existing challenges in the field and outlines promising research directions for the future development of more effective drug delivery strategies in chronic pain management.