From the Guidelines
Systemic Allergic Reaction to Local Lidocaine
Yes, it is possible to have a systemic allergic reaction to local lidocaine, although it is rare, with genuine immunologic reactions representing only 1% of all adverse reactions to these medications 1.
- Symptoms of a systemic allergic reaction may include hives, itching, swelling, difficulty breathing, rapid heartbeat, and a drop in blood pressure.
- If a patient has a known allergy to lidocaine, alternative anesthetics may be considered, such as ester type of local anesthetic, as cross-reaction between amide and ester types is rare 1.
- For patients with a true allergy to lidocaine, injection of 1% diphenhydramine or bacteriostatic saline may be useful as an anesthetic for small excisions and biopsies 1.
- It's essential to start with a low dose and monitor the patient closely for any signs of an allergic reaction, and having emergency equipment and medications, such as epinephrine, readily available is crucial in case of a severe reaction.
- The use of topical, infiltrative, and nerve block anesthesia in combination can be helpful for larger or more complex procedures, but caution should be exercised in patients with known allergies to lidocaine 1.
From the FDA Drug Label
Allergic reactions are characterized by cutaneous lesions, urticaria, edema or anaphylactoid reactions Allergic reactions may occur as a result of sensitivity either to local anesthetic agents or to the methylparaben used as a preservative in the multiple dose vials. Allergic reactions, including anaphylactic reactions, may occur as a result of sensitivity to lidocaine, but are infrequent.
- Systemic allergic reactions to lidocaine can occur, although they are infrequent.
- These reactions may be characterized by cutaneous lesions, urticaria, edema, or anaphylactoid reactions.
- The drug label recommends managing allergic reactions by conventional means 2.
From the Research
Systemic Allergic Reactions to Local Lidocaine
- Local lidocaine (lidocaine hydrochloride) can cause systemic allergic reactions, although such reactions are rare 3, 4, 5, 6, 7.
- These reactions can manifest as anaphylaxis, delayed hypersensitivity, or contact allergy, and may present with symptoms such as urticaria, angioedema, shortness of breath, and cardiac abnormalities 5, 6, 7.
- The incidence of systemic allergic reactions to local anesthetics, including lidocaine, is estimated to be less than 1% 7.
- Skin testing, including prick tests and intradermal tests, can be used to diagnose allergic reactions to lidocaine, but may not always correlate with historical manifestations of hypersensitivity 7.
Cross-Reactions and Alternative Local Anesthetics
- There have been reports of cross-reactions between different local anesthetics, including lidocaine and tetracaine, although the incidence of such cross-reactions is not well established 3.
- In patients with a suspected allergy to lidocaine, alternative local anesthetics such as mepivacaine or bupivacaine may be used, but careful history-taking and allergy testing should be performed to minimize the risk of adverse reactions 4, 5, 6.
- The choice of alternative local anesthetic should be based on the results of allergy testing and the patient's medical history 4, 5, 6.
Diagnosis and Management
- The diagnosis of systemic allergic reactions to local lidocaine should be based on a detailed history, physical examination, and laboratory tests, including skin testing and challenge tests 7.
- The management of patients with suspected allergy to local anesthetics should include careful history-taking, allergy testing, and the use of alternative local anesthetics when necessary 4, 5, 6, 7.