Intradermal study of a new local anaesthetic agent aptocaine.

In a double-blind trial in 28 human volunteers, a new local anaesthetic agent, aptocaine, was compared intradermally at 1, 2 and 3% concentrations with lignocaine 2% and bupivacaine 0.5%. In a second trial in 27 subjects, 1% aptocaine was compared with mepivacaine and prilocaine, both 1, 2 and 3%. In terms of activity as determined by area of anaesthesia, and of duration of action, aptocaine was similar to mepivacaine and more active and long-lasting than lignocaine and prilocaine. By this route aptocaine also appeared longer-lasting than bupivacaine. Duration of action was unaffected by concentration. Aptocaine had marked vasoconstrictor activity, which was maximal at 1%. These local anaesthetic properties suggest that aptocaine merits clinical trials, especially in dentistry.