lidocaine + bupivacaine (4-4-2 ratio)

The 4-4-2 local anesthetic mix is a specific formulation used for pain management during and after voluntary medical male circumcision (VMMC). Developed and studied at International Hospital Kampala, the mixture consists of 4cc of 2% lidocaine (lignocaine), 4cc of 0.5% bupivacaine, and 2cc of water for injection. Both lidocaine and bupivacaine are small molecule local anesthetics that function as sodium channel blockers, inhibiting the initiation and conduction of nerve impulses to provide regional anesthesia. In clinical research, this specific ratio was evaluated in an observational study to compare its efficacy in postoperative pain control against other concentrations, such as a 3-3-4 mixture, which was found to be superior.