Bupivacaine is a long acting local anesthetic in use for many years as a spinal/epidural anesthetic for childbirth and orthopedic procedures, such as hip replacement. It is marketed by AstraZeneca under the trade name Chirocaine. It acts by blocking Na+ channels and also has actions on the heart, which restrict its use by intravenous injection for regional anesthesia.

Chirality and Biological activity

(S)-(-)-enantiomer of bupivacaine

Bupivacaine is a racemic drug. This an example where the distomer shows toxic effect and the need for a switch. The chiral switch of (±)-bupivacaine, , (S)-(–)-enantiomer levobupivacaine, has been developed successfully as a safer local anaesthetic that has the same therapeutic indications as the racemate. Levobupivacaine exhibits less vasodilation and possesses a greater length of action in comparison to bupivacaine. R-Bupivacaine, the distomer, has a greater risk of cardiotoxicity.

Claims justifying the switch

  • Levobupivacaine has decreased risk of cardiotoxicity than the R-form and the racemate
  • Other clinical profiles are essentially similar as the racemate.




Number levobupivacaine heterocyclic ring system. Understand the sterostructure. Look for alternate systematic names.


Chiral switch. Wikipedia, Wikipedia Foundation, 080/08/2022.  https://en.wikipedia.org/wiki/Chiral_switch and references therein

Israel Agranat, Hava Caner and John Caldwell, Nature reviews, Drug Discovery, 1, October,| 753-768, 2002.


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