Drug | Dose | Duration* |
Local anesthetic | ||
Bupivacaine | 8 to 12 mg | 90 minutes |
Ropivacaine | 15 to 20 mg | 90 minutes |
Levobupivacaine | 7.5 to 15 mg | 90 minutes |
Opioids | ||
Fentanyl | 10 to 20 mcg | 3 to 4 hours |
Sufentanil | 2.5 to 10 mcg | 3 to 4 hours |
Morphine | 75 to 150 mcg | 10 to 24 hours¶ |
Hydromorphone | 75 mcg | 5 to 15 hours¶ |
CD: cesarean delivery; NSAIDs: nonsteroidal anti-inflammatory drugs.
* For local anesthetics, duration of action is defined as time to two spinal segment regression. For opioids, duration of action is usually defined as time to first request for analgesia.
¶ Duration of action of hydrophilic opioids varies widely and may depend on administration of systemic analgesics (eg, NSAIDs).