From the Guidelines
The maximum safe dose of lidocaine with epinephrine is 7 mg/kg of body weight. This is based on the most recent and highest quality study available, which recommends not to exceed the maximal toxic doses of local anaesthetics 1. For a 70 kg adult, this equates to approximately 490 mg. Lidocaine with epinephrine is typically available in concentrations of 1% (10 mg/ml) or 2% (20 mg/ml), so the volume limit would be 49 ml of 1% solution or 24.5 ml of 2% solution.
Key Considerations
- The addition of epinephrine (typically 1:100,000 or 1:200,000) allows for this higher maximum dose compared to plain lidocaine (which has a maximum of 4-5 mg/kg) because epinephrine causes local vasoconstriction that slows systemic absorption of lidocaine, reducing toxicity risk and prolonging the anesthetic effect 1.
- When administering, always aspirate before injection to avoid intravascular administration, inject slowly, and be aware that maximum doses should be reduced in elderly patients, those with liver disease, heart failure, or other conditions that might affect drug metabolism or clearance.
- The onset of action is typically 2-5 minutes, with a duration of approximately 1-2 hours for the anesthetic effect and up to 4-8 hours for the analgesic effect.
Important Guidelines
- The maximum safe dose of lidocaine with epinephrine is 7 mg/kg of body weight, as recommended by the most recent guidelines 1.
- For children, no more than 1.5-2.0 mg/kg of lidocaine and 3.0-4.5 mg/kg of lidocaine with epinephrine should be administered in a single treatment 1.
- Use of either ester-type local anesthetics, bacteriostatic normal saline, or 1% diphenhydramine is suggested as an alternate form of local infiltration anesthesia for patients with true allergy to lidocaine 1.
From the Research
Maximum Recommended Dose of Lidocaine with Epinephrine
- The maximum recommended dose of lidocaine is not strictly defined, as it depends on various factors such as the site of injection, patient age, and organ function 2.
- The traditional maximum dose of 200 mg of lidocaine has been recommended for over 50 years, but this is not based on scientific evidence 2.
- When using lidocaine with epinephrine, the dose can be higher due to the vasoconstrictive effects of epinephrine, which reduce the systemic absorption of lidocaine 2.
- A study suggests that the maximum recommended dose of local anesthetic should be based on a milligram of drug per kilogram of body weight, taking into account variables such as body size and cardiovascular compromise 3.
Safety of Lidocaine with Epinephrine in Patients with Cardiac Disease
- Studies have shown that the use of lidocaine with epinephrine in patients with cardiac disease is safe and does not cause significant hemodynamic changes 4, 5, 6.
- A study found that 10 ml of 2% lidocaine with epinephrine 1:100,000 did not cause any significant disturbances in blood pressure or heart rate in patients with ischemic heart disease 4.
- Another study found that lidocaine with epinephrine 1:80,000 did not cause any significant hemodynamic changes in patients with cardiovascular disease 5.
- A comparative study found that 2% lidocaine with epinephrine 1:100,000 did not cause any increase in heart rate or blood pressure and did not cause any arrhythmic changes in patients with cardiac valvular diseases 6.