Penicillin Allergy

PENICILLIN ALLERGY

Penicillin is one of the most commonly prescribed antibiotics. It is part of a family of antibiotics known as beta lactams, and there are many individual medications in this family: Penicillin G, nafcillin, oxacillin, cloxacillin and dicloxacillin, ampicillin, amoxicillin, carbenicillin, ticarcillin, and piperacillin. Anyone who has penicillin allergy  should be presumed to be allergic to all penicillins and should avoid the entire group, unless they have been specifically evaluated for this problem.

Penicillin Allergy Reaction.

Allergic  reactions to Penicillin may range from mildly annoying to life threatening. Penicillin allergy reactions — occurs when the immune system begins to recognize a drug as something "foreign". Several different symptoms can indicate penicillin allergy include : hives (raised, intensely itchy spots that come and go over hours), angioedema (swelling of the tissue under the skin, commonly around the face), throat tightness, wheezing, coughing, and trouble breathing from asthma-like reactions (narrowing of the airways into the lungs), Anaphylaxis — it is a sudden, potentially life-threatening allergic reaction.

Penicillin Allergy Diagnosed

A detailed history is of utmost importance when diagnosing drug allergies. The symptoms, drug history and the timing of reaction in relation to drug administration will help to pinpoint the offending drug and the type of reaction.

Skin testing for penicillin allergy should be done for sensitize patient. The skin is pricked and injected with weak solutions of the various preparations of penicillin and observed for a reaction.

If skin testing is NOT available, options for people who has penicillin allergy  include:

• Take a different antibiotic

·         Challenge test for patient with penicillin allergy(starting with a very small dose of the antibiotic given by mouth. If the person tolerates the smallest dose, a larger dose is given every 30 to 60 minutes until he/she has signs of an allergic reaction or the full dose is given. If the person tolerates the full dose, he or she is not allergic to the antibiotic)

·         Desensitization (a process of giving a medication in a controlled and gradual manner, which allows the person to tolerate it temporarily without an allergic reaction.

Based on study done by Adrian Y. WU Department of Medicine, Queen Mary Hospital,  Patients with penicillin allergy  are 10 times more likely to become allergic to other drugs. This susceptibility not only applies to anaphylactic type reactions, but also extends to drug rashes, exfoliative dermatitis, toxic epidermal necrolysis and Stevens-Johnson syndrome.  So, if you one who has penicillin allergy, the main treatment is avoidance of future use of penicillin and related antibiotics.