I have copied for you below a number of abstracts reporting cases of probable delayed hypersensitivity reactions to local anesthetics. As you .Find information about common, infrequent and rare side effects of Novocain Throwing Up Hives Life Threatening Allergic Reaction Methemoglobinemia .
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Relevance of delayed reactions to injectable lidocaine was definite in cases past, probable, and unknown in case each and possible in cases. Delayed hypersensitivity to lidocaine may present as “suture allergy,” treatment failure, typical contact allergy, or other local skin or dental reactions..An allergic reaction is the medical emergency that can make the most noticeable changes in a patient`s appearance in a matter of minutes. The reactions range from mild rash to a combination of the most serious manifestations of anaphylaxis..