Which local anesthetic has the longest duration of action?

Bupivacaine is known for its long duration of action compared to other local anesthetics. Its extended effects are due to its unique molecular structure, which allows for a slow release from the nerve tissues after it has been deposited. This property makes it especially useful in procedures that demand a prolonged anesthesia period, such as certain surgical interventions or in managing postoperative pain.

When administered with a vasoconstrictor like epinephrine, the duration of action can be further enhanced since epinephrine reduces blood flow to the area, thereby slowing the absorption of the anesthetic into the systemic circulation. This combination allows bupivacaine to provide effective and prolonged pain relief, often lasting several hours, which is significantly longer than the durations associated with other local anesthetics, including prilocaine, articaine, and lidocaine.

The other local anesthetics listed typically have shorter durations of action, thus making bupivacaine the preferred choice for situations requiring extensive or long-lasting anesthesia. Understanding these differences helps in choosing the most effective anesthetic for particular dental or medical procedures.