Ropivacaine

Brand Names: Naropin, Ropivacaine HCl

Drug Class: Amide local anesthetic

Overview

Ropivacaine is a long-acting amide local anesthetic with a duration of action of 2-6 hours. It produces reversible conduction blockade of nerve impulses by inhibiting sodium ion influx through voltage-gated sodium channels in neuronal cell membranes. It has a lower risk of cardiotoxicity compared to bupivacaine due to its S-enantiomer structure and lower lipid solubility.

Mechanism of Action

Blocks sodium ion influx through voltage-gated sodium channels in neuronal cell membranes, preventing depolarization and propagation of nerve impulses.

Indications

  • Surgical anesthesia (epidural, nerve block, infiltration)
  • Acute pain management (postoperative, labor pain)
  • Chronic pain management (via continuous epidural infusion)

Dosage

Dosage varies by procedure: Epidural anesthesia: 15-30 mL of 0.5-1% solution; Nerve block: 5-40 mL of 0.5-0.75% solution; Infiltration: 1-100 mL of 0.2-0.5% solution. Maximum recommended dose: 200 mg (or 2.5 mg/kg) as single injection; 770 mg/24 hours for continuous infusion.

Contraindications

  • Hypersensitivity to amide local anesthetics
  • Severe hypotension
  • Complete heart block
  • Epidural anesthesia contraindications (coagulopathy, infection at injection site)

Side Effects

  • Hypotension
  • Bradycardia
  • Nausea/vomiting
  • Back pain
  • Headache
  • Fever
  • Urinary retention
  • Paresthesia
  • Methemoglobinemia (rare)

Interactions

  • Class I antiarrhythmics (increased cardiac toxicity)
  • Other local anesthetics (additive toxicity)
  • MAO inhibitors, tricyclic antidepressants (hypotension risk)
  • Vasoconstrictors (epinephrine may prolong duration)