Which local anaesthetic is known to have the greatest content of adrenaline as a vasoconstrictor?

The local anesthetic recognized for having the highest concentration of adrenaline as a vasoconstrictor is Lidocaine. The presence of adrenaline (also known as epinephrine) in local anesthetics is crucial because it helps to constrict blood vessels, which prolongs the duration of anesthesia, minimizes bleeding at the surgical site, and generally enhances the effectiveness of the anesthetic.

Lidocaine is commonly used with adrenaline to achieve these benefits, typically at a concentration of 1:100,000 or 1:200,000. The physiological role of adrenaline here is to maintain a localized effect of the anesthetic by reducing blood flow away from the area, thus extending its duration and effectiveness.

While other local anesthetics also contain adrenaline, they usually have lower concentrations or are formulated differently, making Lidocaine with adrenaline the standard option that is noted for having the greatest content. This characteristic makes it a preferred choice in many dental procedures where bleeding control and prolonged analgesia are beneficial.