Q:

11/23/2019
A 47 year-old female presents for Lidocaine testing. Historically, she c/o crying and shaking after Novacaine x 2 years ago. She c/o extreme fatigue (needing to be picked up from the office and sleeping until the next a.m.) after getting her eyes dilated (which is often seen) but had Altaflor (numbing agent to check her glaucoma score) (Benoxinate HCL=numbing agent) each time. All of the above are obvious: 1.) Do not use Novacaine and 2.) her reaction was typical for dilation not the numbing agent.

She presented with h/o a weird reaction when undergoing a breast biopsy. According to her, when the MD first numbed the area with Lidocaine, she was fine, but once he injected more, she lost her ability to speak, collapsed on the ground and awoke bare chested on the ground surrounded by doctors and heard one comment that they finally found a pulse. I obtained the records from the breast center. They described a vasovagal response, and stated they were able to get the BX done but unable to 'tag' the site. No meds were given. She describes herself as not being an anxious person.

I cannot account for her reaction. I feel uncomfortable doing Lidocaine challenge in my office and feel that it should be done in a hospital setting. Your thoughts?

A:

Patients with suspected allergic reactions to local anesthetics should undergo allergy evaluation because most do not truly have allergy to these medications. There are case reports of anaphylaxis to local anesthetics in the literature but this is a very infrequent problem. Skin testing and subcutaneous challenge are performed to evaluate these reactions and also identify safe alternative local anesthetic agents. If testing with a local anesthetic is negative in the face of a convincing history, then one should investigate for other possible culprits. In the case of your patient, it is reasonable to perform skin testing in your office. This could be done for lidocaine (to further evaluation the possibility of an IgE-mediated reaction) but more importantly, the patient should be tested with an alternative, non-amide local anesthetic. If testing to a non-amide local anesthetic is negative, then incremental challenge should be performed to assess if it is tolerated. It may not be necessary to perform a lidocaine challenge, but if it were to be deemed necessary, then I agree with you that it would be best performed in a hospital setting.

I hope this information is helpful to you and your patient.
Jacqueline A. Pongracic, MD, FAAAAI

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