Adjuvant agents in regional anaesthesia

Regional anaesthesia forms an important part of anaesthesia and pain management. A wide variety of adjuvant agents are used along with local anaesthetic mixtures to enhance and prolong their actions. In this article we examine the adjuvants used in current clinical practice in the UK: the commonly used opioids as well as non-opioid drugs. Opioids are discussed in greater detail as they are the most researched. The mechanism of action of each drug is discussed and the most popular routes of administration are mentioned. Evidence for clinical effectiveness is also covered. The commonly encountered adverse effects and precautions that should be considered are also cited.