penicillin allergy


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penicillin allergy

A hypersensitivity reaction to penicillin, present in about 0.5% to 8% of the population. Although different types of hypersensitivity reactions may occur, the most common and potentially dangerous are the type I (immediate) reactions mediated by immunoglobulin E. If a patient reports a history of signs of local anaphylaxis (such as urticaria) or systemic anaphylaxis (such as bronchoconstriction, vasodilation) after taking penicillin, no penicillin or other beta-lactam antibiotics (such as cephalosporins) should be given to that patient ever again. In those very rare situations in which an infection is susceptible to no other antibiotic and the infection is serious enough to risk the danger of anaphylaxis, the patient may be desensitized with gradually increasing doses of penicillin.
See also: allergy
References in periodicals archive ?
In one of those studies, which was published this year in an allergy and asthma journal, 20 subjects with a history of penicillin allergy agreed to direct oral amoxicillin rechallenge by an allergist, he said.
The study compared adults with a known penicillin allergy to similar people without a known penicillin allergy.
After adjusting for several known risk factors, the researchers found that a penicillin allergy label was associated with a 69 percent increased risk of MRSA and a 26 percent increased risk of C difficile.
Torres et al., "Clinical evaluation of Pharmacia CAP system[TM] RAST FEIA amoxicilloyl and benzylpenicilloyl in patients with penicillin allergy," Allergy, vol.
The parents (597) of children aged 4-18 years with a history of parent-reported penicillin allergy completed an allergy questionnaire; 51% (302) of the children were categorized as low risk, and 100 of them completed allergy testing by using a standard three-tier testing process.
The second part of the study was conducted in 2014, and it prospectively included patients with a history compatible with IgE mediated penicillin allergy, namely a history of urticaria/angioedema, anaphylaxis or rash during penicillin, amoxicillin or amoxicillin-clavulanic acid treatment.
Overdiagnosis of penicillin allergy is not benign, Ramsey says.
There is no defined azithromycin paediatric dosage for the secondary prevention of rheumatic fever in penicillin allergy. Azithromycin has however been dosed long term in clinical trials in children with cystic fibrosis.
(19) observed an association between levels of specific IgE, cytokines and polymorphisms of IL-4 C/T and IL-4R[alpha]Q576R in patients with penicillin allergy. According to the authors, the allele LL-4R[[alpha].sup.*]Q576 was present more frequently in allergic patients than in control subjects.
This is a good time to mention that there is potential cephalosporin cross-sensitivity in patients with a true penicillin allergy (4% to 10% of cases) that has been observed predominantly with first-generation cephalosporins.
There is also a "traffic-light" system identifying which antibiotics should not be given to patients with penicillin allergy.
Penicillin allergy is one of the most commonly reported drug allergies worldwide.