Phenobarbital allergic reactions

Hypersensitivity Allergic reactions occur, especially in persons with asthma, urticaria, angioedema, or similar conditions. Hypersensitivity reactions include localized swellings, particularly of the eyeUds, cheeks, or Ups, and erythematous dermatitis. Rarely, exfoliative dermatitis may be caused by phenobarbital and can prove fatal the skin eruption may be associated with fever, deUrium, and marked degenerative changes in the liver and other parenchymatous organs. 

Pseudoallergic reactions resemble allergic reactions clinically but are not immunologically mediated. Examples include asthma and rashes caused by aspirin and maculopapular erythematous rashes due to ampicillin or amoxicillin in the absence of penicillin hypersensitivity. Few other entities that can initiate this reaction are sulfonamides, anticonvulsants (phenytoin, carbamazepine and phenobarbital), NSAIDs (aspirin, naproxen, nabumetone and keto-profen), antiretroviral agents and cephalosporins [1 ]. 

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