From the Guidelines
The recommended maximum dosage of lidocaine as a local anesthetic is 7 mg/kg with epinephrine and 4.4 mg/kg without epinephrine. When administering lidocaine, it's essential to calculate the total dose based on the concentration of the solution being used (typically available as 1%, 2%, or 4% solutions) 1. The addition of epinephrine causes local vasoconstriction, which slows systemic absorption of lidocaine, thereby reducing toxicity risk and prolonging the anesthetic effect.
Some key points to consider when using lidocaine include:
- Maximum recommended doses and durations of action are shown in the guidelines, with lower doses recommended for very vascular areas 1.
- Doses of amides should be decreased by 30% in infants younger than 6 mo 1.
- When lidocaine is being administered intravascularly, the dose should be decreased to 3 to 5 mg/kg; long-acting local anesthetic agents should not be used for intravenous regional anesthesia 1.
- The use of local anesthetic agents in pediatric patients requires particular attention to cumulative dosage, and lower doses should be used in very vascular areas 1.
It's crucial to follow these guidelines to minimize the risk of systemic toxicity, which can manifest as CNS symptoms (dizziness, seizures) and cardiovascular effects (hypotension, arrhythmias) 1. By prioritizing careful dosing and adhering to the recommended maximum dosages, healthcare providers can ensure the safe and effective use of lidocaine as a local anesthetic.
From the FDA Drug Label
Adults For normal healthy adults, the individual maximum recommended dose of lidocaine HCl without epinephrine should not exceed 4. 5 mg/kg (2 mg/lb) of body weight Pediatric Patients It is difficult to recommend a maximum dose of any drug for pediatric patients, since this varies as a function of age and weight For children over 3 years of age who have a normal lean body mass and normal body development, the maximum dose is determined by the child’s age and weight. The recommended local anaesthetic dosage per kg of lidocaine is:
- 4.5 mg/kg for normal healthy adults 2
- For pediatric patients, the dose is determined by the child’s age and weight, but should not exceed 1.5 to 2 mg/lb (approximately 3.3 to 4.4 mg/kg) for children over 3 years of age 2
From the Research
Local Anaesthetic Dosage per kg
- The recommended local anaesthetic (LA) dosage per kilogram (kg) of lidocaine is not explicitly stated in the provided studies as a specific value, but rather as a range of doses that are considered safe and effective 3, 4.
- According to 3, the maximum recommended dose of lidocaine is 200 mg, but this value has remained unchanged for over 50 years and may not be evidence-based.
- Study 4 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.
- However, the exact dosage per kg of lidocaine is not provided in the studies, and it is recommended to consider the specific patient factors and the site of injection when determining the appropriate dose 3, 5, 6, 7.
- In general, the dosage of lidocaine can range from 0.25% to 1% with epinephrine, and the onset and duration of action can vary depending on the specific mixture and concentration used 5, 6, 7.