Transdermal Delivery of Drugs for Acute and Chronic Pain

Pain is universal, it contributes substantially to morbidity, mortality, and disability, and is a serious health problem. Acute pain usually lasts less than 7 days, but often lasts up to 30 days, and may recur periodically. Chronic pain, defined as lasting more than 3 months, affects approximately 50 million people and generates costs of $635 billion. The problems related to inadequate pain management are frequent and important, so much so that emphasis has been given to the effective delivery of drugs through the skin. This organ has been studied extensively over the last decade because it is easily accessible and would help to solve the problem. It is evident that there is a need to improve transdermal drug delivery (TDD) as it offers multiple advantages, they are noninvasive, can be self-administered, and provide prolonged release. This chapter recapitulates the history of transdermal drug delivery and focuses on addressing the inadequate management of acute and chronic pain.