Local Anesthetic Guidelines

Precautions and Alternatives

• When using any local anesthetic, be vigilant for signs of toxicity including tinnitus, light-headedness, and tingling of tongue/lips, and monitor for signs of local anesthetic systemic toxicity (LAST) 1, 2, 3
• The American Academy of Dermatology and the American Academy of Pediatrics recommend alternative forms of local infiltration anesthesia, including ester-type local anesthetics (e.g. procaine, tetracaine, benzocaine), diphenhydramine, and bacteriostatic saline, for patients with true lidocaine allergy or other concerns, with considerations for onset of action, efficacy, and potential for systemic toxicity 2, 3
• Ester-type local anesthetics are suitable for small excisions and biopsies, and have a low risk of cross-reactivity with amide-type anesthetics like lidocaine, making them a preferred first-line option for patients with confirmed lidocaine allergy 2
• Bacteriostatic saline is less painful than diphenhydramine when injected with epinephrine, and is useful for small excisions and biopsies, but may not be suitable for longer procedures 2
• The American Academy of Dermatology recommends using the lowest effective dose of alternative anesthetics, aspirating before injection, and monitoring for signs of LAST, to minimize the risk of systemic toxicity 2, 3
• Genuine immunologic reactions to lidocaine are rare, representing only 1% of all adverse reactions, and many reported "allergies" are actually vasovagal reactions or anxiety responses, highlighting the importance of confirming true allergy before selecting an alternative anesthetic 2
• For procedures requiring longer duration, the American Academy of Dermatology recommends considering ropivacaine if no cross-reactivity concern exists, and using ester-type local anesthetics or other alternatives as needed 2

Signs and Symptoms of Toxicity

• Early symptoms of local anesthetic systemic toxicity (LAST) include circumoral numbness, facial tingling, slurred speech, and metallic taste, while progressive symptoms include seizures, CNS depression, and cardiac failure, according to the American Academy of Dermatology 2

Special Populations

• The American Academy of Pediatrics recommends using alternative anesthetics, such as ester-type local anesthetics (e.g. chloroprocaine), for children, with appropriate dose adjustments, and considering the use of continuous epidural techniques in infants and children 3