DRUG ALLERGIES STUDY

It’s a question every patients is asked by every doctor who examines them--is there a history of a drug allergy? While many patients believe they might have a significant drug allergy that precludes them from getting that medication, new research in fact says otherwise,

Eli Schenfield had a recent medical procedure and was prescribed a type of penicillin.
“My reaction to the pill was as if all the oxygen was sucked out of the air,” says Eli. It’s guessed what happened was that he had an allergic reaction to the drug. But it’s not certain. New research shows a presumed drug allergy, in fact, one that is thought to be severe, often does not really exist. Dr. Jonathan, Field, an allergist and immunologist says, “Five out of every hundred people are allergic. However the severities of drug allergies vary. Some people have a little rash, some people have a life threatening reaction.”
The study, published in the latest Annals of Internal Medicine, showed that among more than 1300 drug sensitivity tests specifically looking for a highly suspected severe drug allergic reaction, only 17% turned out to be positive. “Life threatening reactions include loss of consciousness, asthma and seizures,” informs Dr. Field.
More than half of these so called immediate drug allergies will occur in the first hour after receiving the medication, according to the research. Nearly all occur in the first 24 hours, an important point because many less severe drug allergic reactions occur after this period of time. “The non-immediate reactions are the typical rashes you’ll hear patients commonly describe after three or four days. The rashes are usually non-immediate, they have a different mechanism, and they tend not to be life threatening,” states Dr. Field.
The most common severe drug allergic reaction was urticaria, or a severe rash of hives, which occurred in 2/3rds of the patients with a positive test. The test was most often positive for a severe reaction when the suspected drug was aspirin. Other anti-inflammatories, like ibuprofen, are positive in just over a quarter of those tested. Antibiotics are not as common a cause of severe drug allergies as aspirin and the other anti-inflammatory medications, in spite of the fact many patients report them and then they are excluded from the patient’s care. And penicillin-type medications, which are commonly reported as a cause of drug allergies, are not even the most common antibiotic class which cause allergies. In the study, less than one in every ten persons who believed they had a severe allergy to penicillin actually had one.
“It’s most important to be able to characterize what happened, not just assume I was told as a kid I was allergic,” recommends Dr. Field.
If a drug allergy is suspected, the easiest course is to simply avoid the medication, which was done with the patient we saw in the story. But in those cases where the drug has no replacement, say in the case of aspirin, and you want to use that medicine in the patient, then testing should be done. And if it’s an antibiotic that’s absolutely needed and there is no adequate replacement, you can desensitize someone temporarily to the medication so they can take it without having an allergic reaction. That desensitization process needs to be done in a hospital setting though.
Because the reaction was recent and known, Eli’s doctor recommended to simply avoiding the antibiotic. “Drug allergies can be difficult to live with. I have to constantly remind myself that I’m that I’m allergic to penicillin,” Eli says.