Local Anesthesia Dose Calculator
- Input the patient's weight.
- Select the anesthetic agent(s) (select "None" for second agent if using only one).
- Optionally select a buffer ratio for each agent (NaHCO₃ buffering).
- If using a second agent, input the estimated dose.
Results
This calculator provides guidance based on published recommendations.1, 2 Always double check and err on the side of caution. Clinical judgment by a physician is required in every situation. The user assumes all responsibility for decisions made with the information provided by this app. The maximum recommended doses displayed are for otherwise healthy adults. For patients with the following conditions, dose reductions may be necessary:3
- Age Extremes (< 4 months or > 70 years)
- Severe Renal Dysfunction
- Hepatic Dysfunction
- Advanced Heart Failure
- Pregnancy
Adjusted maximum doses of local anesthetic combination
Local anesthetic properties and max doses1
| Anesthetic | Onset (min) | Duration (min) | Maximum recommended dose for adults | ||
|---|---|---|---|---|---|
| Without epi | With epi | Without epi | With epi | ||
| Amides | |||||
| Articaine | 2-4 | 30-120 | 60-240 | 5.0 mg/kg or 350 mg | 7.0 mg/kg or 500 mg |
| Bupivacaine | 2-10 | 120-240 | 240-480 | 2.5 mg/kg or 175 mg | 3.0 mg/kg or 225 mg |
| Etidocaine | 3-5 | 200 | 240-360 | 4.5 mg/kg or 300 mg | 6.5 mg/kg or 450 mg |
| Lidocaine | <1 | 30-120 | 60-240 | 4.5 mg/kg or 300 mg | 7.0 mg/kg or 500 mg |
| Mepivacaine | 3-20 | 30-120 | 60-240 | 6.0 mg/kg or 400 mg | 7.0 mg/kg or 550 mg |
| Prilocaine | 5-6 | 30-120 | 60-240 | 7.0 mg/kg or 400 mg | 10.0 mg/kg or 600 mg |
| Esters | |||||
| Chloroprocaine | 5-6 | 30-60 | N/A | 11.0 mg/kg or 800 mg | 14.0 mg/kg or 1000 mg |
| Procaine | 5 | 15-90 | 30-180 | 10.0 mg/kg | 14.0 mg/kg |
| Tetracaine | 7 | 120-240 | 240-480 | 2.0 mg/kg | 2.0 mg/kg |
Disclaimer from the article that shared the above table:1
"Adherence to these guidelines will not ensure successful treatment in every situation. Furthermore, these guidelines should not be interpreted as setting a standard of care, or be deemed inclusive of all proper methods of care reasonably directed to obtaining the same results. The ultimate judgment regarding the propriety of any specific therapy and/or technique must be made by the physician and the patient in light of all the circumstances presented by the individual patient, and the known variability and biological behavior of the disease. This guideline reflects the best available data at the time the guideline was prepared. The results of future studies may require revisions to the recommendations in this guideline to reflect new data."
The values used for calculations are for adults only and are higher than recommended for pediatric patients. For example, the recommended maximum dose of lidocaine in pediatric patients is 1.2–2 mg/kg without epinephrine and 3–4.5 mg/kg with epinephrine.
LAST is a rare but potentially life-threatening event resulting from systemic absorption of local anesthetic agents. Clinicians must be vigilant for early signs and symptoms, which can progress rapidly. Initial manifestations often involve the central nervous system, including circumoral numbness, metallic taste, lightheadedness, visual and auditory disturbances, and anxiety. This can be followed by more severe CNS toxicity such as drowsiness, slurred speech, muscle twitching, and ultimately, seizures. Cardiovascular involvement may present with hypertension and tachycardia initially, followed by hypotension, bradycardia, various arrhythmias, and potentially cardiac arrest.
This calculator provides guidance on maximum recommended dosages based on established guidelines and patient factors. However, it is the sole responsibility of the administering physician to carefully consider individual patient characteristics, employ meticulous injection techniques, and continuously monitor for any signs or symptoms of LAST throughout the procedure and immediate post-procedural period. Prompt recognition and appropriate management, including immediate cessation of local anesthetic administration and adherence to established treatment protocols, are critical in mitigating the risks associated with LAST.
References:
- Kouba DJ, LoPiccolo MC, Alam M, et al. Guidelines for the use of local anesthesia in office-based dermatologic surgery. J Am Acad Dermatol. 2016;74(6):1201-1219.
- Budney SM, Holcombe TC. A Visual Method for the Safe Administration of Multiple Local Anesthetics. Plast Reconstr Surg Glob Open. 2019;7(6):e2294.
- Rosenberg PH, Veering BT, Urmey WF. Maximum recommended doses of local anesthetics: a multifactorial concept. Reg Anesth Pain Med. 2004;29(6):564-524. doi:10.1016/j.rapm.2004.08.003