Bupivacaine 0.5% Injection 50 mg Per 10 ml x 25 Vials (RX)Bupivacaine 0. 5% Injection (50 mg per 10 mL) Bupivacaine is a potent amide type local anesthetic used by clinicians for regional anesthesia. Each mL of a 0. 5% solution contains 5 mg of bupivacaine (so a 10 mL vial has 50 mg). It blocks nerve impulse conduction by binding to open voltage gated sodium channels in nerve membranes, stabilizing their inactive state and preventing depolarization. Bupivacaine has a relatively slow onset (often 1020 minutes