Local anesthetic allergy

Wasserfallen JB. Frei PC Long-term evaluation of 39 usefulness of skin and incremental challenge tests in patients with history of adverse reaction to local anesthetics. Allergy 1995 50 162-165. 

Benzocaine can cause sensitization, and being a para-aminobenzoic acid derivative it can cross-react with para-phenylenediamine, sulfonamides, aniline dyes, and related local anesthetics. However, in a recent retrospective study of 5464 patients it was concluded that benzocaine allergy is not common in the UK, confirming earlier reports that benzocaine should not be used as a single screening agent for local anesthetic allergy (27). 

Scala E, Giani M, Pirrotta L, Guerra EC, Girardelli CR, De Pita O, Puddu P. Simultaneous allergy to ampicillin and local anesthetics. Allergy 2001 56(5) 454-5. 

Immunologic Allergic reactions to lido-caine for fiberoptic bronchoscopy have been reviewed [57 ]. The authors concluded that lidocaine is safe in bronchoscopy, provided that care is taken to limit the dose. In suspected local anesthetic allergy they suggested patch testing before the use of any topical anesthesia. 

Yamamoto F, Hamburger RN Administration of 27 local anesthetics to patients with a history of prior adverse reaction. J Allergy Clin Immunol 1978 61 339-345. 28... 

Breit S, Rueff F, PrzybiUa B Deep impact contact allergy after subcutaneous injection of local anesthetics. Contact Dermatitis 2001 45 296-297. Orasch CE, Helbling A, Zanni MP, Yawalkar N. Hari Y Pichler WJ T-cell reaction to local anaesthetics relationship to angioedema and urticaria after subcutaneous application-patch testing and LTT in patients with adverse reaction to local anaesthetics. Clin Exp Allergy 1999 29 1549-1554. 

Ruzicka T, Gerstmeier M, PrzybiUa B, Ring J Allergy to local anesthetics comparison patch test with prick and intradermal test results. J Am Acad Dermatol 1987 16 1202-1208. 

GaU H, Kaufmann R. Kalveram CM Adverse reactions to local anesthetics analysis of 197 cases. J Allergy CUn Immunol 1996 97 933-937. 

Aldrete JA, O Higgins JW Evaluation of patients with history of allergy to local anesthetic drugs. South Med J 1971 64 1118-1121. 

De Shazo RD, Nelson HS An approach to the 38 patient with a history of local anesthetic hypersensitivity experience with 90 patients. J Allergy Chn Immunol 1979 63 387-394. 

Berkum Y. Ben-Zvi A. Levy Y. Galili D. Shalit M Evaluation of adverse reactions to local anesthetics experience with 236 patients. Ann Allergy Asthma Immunol 2003 91 342-345. 42... 

The answer is c. (Hardman, p 340. Katzung, p 437.) Of the listed agents, only bupivacaine is an amide. Allergy to amide-type local anesthetics is much less frequent than with ester-type local anesthetics, such as benzo-caine patients who demonstrate an allergy to one such drug will be allergic to all of them... 

Several of the older generation antihistamines are used exclusively for situations that do not involve an allergic reaction. For example, some demonstrate significant antiemetic, antimotion sickness, antiparkinsonian, antitussive, and local anesthetic actions (some Hj antagonists are more potent than procaine). They can be found in many OTC products, particularly for the relief of symptoms from the common cold and allergies, as well as by prescription. The effectiveness of the agents in the treatment of motion sickness and Parkinson s disease may be attributed to their anticholinergic actions. 

Practitioners should record the event in the patient s chart and avoid using the same anesthetic on subsequent patient visits. Because there is apparently little cross-sensitivity between classes of local anesthetics, practitioners can usually change from proparacaine to an ester of PABA, or vice versa, with little risk of local allergy. Unfortunately, no topical anesthetics approved for ocular use have an amide linkage. Such anesthetics, because of their extremely low allergenic potential, would serve as ideal topical ocular anesthetics. 

Systemic hypersensitivity reactions are not a frequent problem in local anesthesia. Systemic toxicity or allergy to additives (hyaluronidase, bisulfate, parabens) has sometimes been mistakenly classified as hypersensitivity to local anesthetics (SEDA-17,135) (29). WeU-documented case reports are very few, relating particularly to the older aminoesters this appears to be because these agents have the highly antigenic para-aminobenzoic acid as a metabolite (SEDA-13, 98). The incidence of true allergy is actually very low, probably less than 1% of all the adverse effects attributable to these substances (SEDA-20, 123). 

When injected into the skin, local anesthetics often cause pseudo-allergic reactions, with similar symptoms to immediate type allergy (42). However, true immediate hypersensitivity to local anesthetics is extremely rare. 

Redfern DC. Contact sensitivity to multiple local anesthetics. J Allergy Clin Immunol 1999 104(4 Pt 1) 890-1. 

Breit S, Rueff F, PrzybiUa B. Deep impact contact allergy after subcutaneous injection of local anesthetics. Contact Dermatitis 2001 45(5) 296-7. 

Aldrete JA, Johnson DA. Allergy to local anesthetics. / Am Med Assoc 1969 207 356-357. 

Allergies to local anesthetics (LAs) are rare, and the term allergy is often used to describe numerous problems that are more likely an overdose or a vagal reaction. Publications report that the frequency of allergic reactions to LAs is no more than 1% of aU the side-effects met with. Lidocaine is an amide local anesthetic that does not cause many allergies. 

Lidocaine, mexiletine, and tocainide rarely cause typical local anesthetic toxicity (ie, CNS stimulation, including convulsions) cardiovascular depression (usually minor) and allergy (usually rashes but may extend to anaphylaxis). Tocainide may cause agranulocytosis. These drugs may also precipitate arrhythmias, but this is less common than with class lA drugs. Hyperkalemia increases cardiac toxicity. 

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