Drug hypersensitivity affects 8% of French people. These are discomforts and symptoms that occur after taking medication, and which most often come from an intolerance.
Martin Ducret, doctor and journalist at Doctor’s Daily, evoked today drug hypersensitivity, which affects 8% of French people, and particularly the confusion between an allergy and an intolerance to a drug.
franceinfo: Already, what is drug hypersensitivity?
Martin Ducret: Drug hypersensitivity is the appearance of symptoms – mostly skin reactions such as pimples, hives, itching, or swelling of the eyelids or face – after taking a drug. Most often an antibiotic or an anti-inflammatory.
Contrary to popular belief, this hypersensitivity is mainly due to an intolerance, not an allergy?
Yes, allergy – which is a disorder of the immune system caused by the production of antibodies or specialized cells, T lymphocytes – is the cause in only 10% of cases.
This therefore means that the vast majority of skin reactions, which occur after taking a drug, are due to an intolerance. In this case, no antibodies, no T lymphocyte, it is directly the drug itself that creates the problem. It looks like an allergy, but it’s not!
Why is it important to make this distinction, if the two are so similar?
“Because an allergy can be serious, while an intolerance is just unpleasant”, explained to me Dr. Brigitte Jallut, dermatologist in Avignon. “It’s quite rare, but an allergy can cause a severe immune system reaction that can lead to death.” The distinction is therefore essential!
To understand this, let’s take the example of penicillin allergy. I regularly have patients who tell me: “I am allergic to penicillin, I had pimples and itchy spots when I was a child”. If it really is an allergy, taking penicillin is contraindicated for life! But if it is an intolerance, which is the most common, penicillin can be taken again without danger. Especially since intolerance can occur during one intake, but not necessarily during the following ones.
So in case of secondary skin reaction to a drug, even old, you must consult an allergist to differentiate an allergy from an intolerance!