[ \text{Maximum volume (mL)} = 0.7 \times \text{weight (kg)} ]

Subject to the 50 mL / 500 mg cap.

For larger-field infiltration, dilute 1% lidocaine with epinephrine using normal saline while keeping the total lidocaine amount within the calculated limit. A commonly used dilution is 0.5% lidocaine with epinephrine, which allows twice the volume but not twice the lidocaine dose.

Allow approximately 25-30 minutes after injection for maximal epinephrine vasoconstriction before incision. Be prepared to treat local-anesthetic systemic toxicity and have phentolamine available for rare persistent epinephrine-related digital ischemia. Use added caution or avoid WALANT in severely compromised digital circulation, such as significant peripheral vascular disease or vasospastic disorders.

Source: Campbell's Operative Orthopaedics, 15th ed., WALANT section; the WALANT state-of-the-art review also describes the commonly recommended 7 mg/kg limit.