Which of these drugs contains an ester group?

Articaine is notable for its unique structure that includes an ester group, which is one of the distinguishing features among local anesthetics. This ester group differentiates it from many other common local anesthetics, which are typically amides. The presence of the ester linkage in articaine contributes to its metabolism; it is hydrolyzed in the plasma, leading to a shorter duration of action compared to amide local anesthetics that are primarily metabolized in the liver.

The ester local anesthetics tend to exhibit different profiles in terms of how they are processed in the body and their potential for allergic reactions. Articaine, while primarily classified as an amide due to its thiophene ring, retains that ester component, which makes it particularly effective in terms of onset and potency, and is utilized frequently in dental procedures.

In contrast, lidocaine, mepivacaine, and prilocaine all belong to the amide class of anesthetics, characterized by their amide linkages and different metabolic pathways. This distinction is crucial for practitioners to consider when selecting an anesthetic agent for different procedures, especially with regard to patient allergies and the desired duration of anesthesia.