In the event of an allergy to an antibiotic, practitioners are forced to opt for alternative molecules which may be less effective, present more side effects or encourage the emergence of bacterial resistance. However, nine out of ten people who say they are allergic to antibiotics are not in reality…
Nearone in ten people think they are allergic to certain antibioticsaccording to studies carried out on the subject.
This information is often recorded in the personal medical file, consulted by health professionals. However, in more than nine cases out of ten, said allergy to antibiotics does not existthe symptoms which gave rise to the suspicion of allergy actually arising from other problems.
However, wrongly thinking oneself allergic to antibiotics can have deleterious consequences for his healthin particular because this can deprive the patients concerned of effective treatments.
What is an allergy to antibiotics?
Antibiotic allergies are the result of inappropriate reactions of the immune system. There are some two types : immediate allergies and delayed allergies.
THE immediate allergies are due to specific antibodies (IgE). They occur instantly, but result from prior, asymptomatic sensitization, which may have occurred years earlier, following a first encounter with the molecule causing the allergy (often in childhood, even during intrauterine life).
Delayed allergies occur 48 to 72 hours after taking the antibiotic. They do not involve antibodies, but immune cells, T lymphocytes. They generally result in a rash of varying severity.
In the event of an allergy, the type of reaction that occurs is unique to each person. Exceptionally, the allergic reaction can be serious, with a risk of death, due, for example, to anaphylactic shock (a immediate exacerbated generalized allergic reaction). However, the non-serious reactionssuch as skin rashes, are the most common.
Which is usually not an allergy to antibiotics
After taking antibiotics, symptoms may appear without these being an allergic reaction. Indeed, like any medication, antibiotics can produce various side effects.
The most common are nausea, diarrhea or fungal infections. Examples include oral or vaginal candidiasis, mycoses caused by microscopic fungi (yeasts belonging to the genus Candida), which proliferate by taking advantage of the fact that antibiotics disrupt the bacterial flora with which they usually compete.
These adverse effects do not contraindicate treatment with antibiotics, and can be managed by treatments.
Furthermore, you should also know that the majority of skin rashes are not of allergic origin either, but are often due to the initial infection. Particularly in children, febrile skin rashes may be due to viruses (particularly parvovirus B19 and the virus roseola).
It should also be noted that patients suffering from infectious mononucleosisdisease caused by the EBV virus (Epstein-Barr virus), can sometimes also receive antibiotics (while they are not effective on viruses), particularly due to diagnostic difficulties. It is therefore common for a rash to occur after taking amoxicillin, without it being an allergy to this antibiotic.
Wrongly believing oneself to be allergic is not without risk
The answer is simple: wrongly believing oneself to be allergic to penicillin is a considerable potential loss of chance in the event of infection.
Indeed, when a prescriber thinks he cannot use an antibiotic indicated as first line in the recommendations for your diseasehe turns to another antibiotic, usually from a different family.
However, often these alternatives are not only less effective, but also more toxic, that is to say higher risk of side effects. Additionally, these alternative antibiotics are often more generators of antibiotic resistanceselecting more than antibiotic resistant bacteria in microbiotanotably the intestinal flora.
The case of penicillin and its derivatives (such as amoxicillin) is emblematic in this respect: the most frequent allergies to antibiotics concern this family. However, these antibiotics are the most widely used. Depriving yourself of it greatly complicates the treatment of infections.
Note also that due to the high risks of cross allergies between antibiotics belonging to the same family (such as penicillin and its derivatives – such as amoxicillin), a patient who claims to be “allergic to” will not be prohibited from a single molecule, but an entire class of antibiotics…
Studies have shown that patients considered allergic to penicillin antibiotics have an increased risk of dying from a bacterial infection and to be reached by infections that are difficult to treatbecause due to bacteria resistant to multiple antibiotics.
How to clearly differentiate an allergy from other adverse effects?
THE antibiotics can have different types of side effectslinked to three main mechanisms:
- allergic, described above, which can concern all antibiotics;
- toxic, the manifestations of which are specific to each antibiotic. For example, we can cite the risk of joint pain or tendonitis associated with taking fluoroquinolones;
- of disruption of the microbiota (a microbiota is all the microorganisms that live in a given environment — in this case our body): this mechanism concerns all antibiotics, and results in a risk of diarrhea, mycosis andantibiotic resistance (emergence of bacteria resistant to antibiotics).
In the majority of cases, the precise description of the reaction to the antibiotic (notably the type of symptoms and their onset time) allows the healthcare professional to know whether it is an allergy to an antibiotic, and to determine the type of allergy in question (and therefore its potential seriousness).
Some cases can sometimes be more complex to diagnose. They then require specialist advice from an allergist, who can use specific tests if necessary (often skin tests).
Can antibiotic allergies go away over time?
It is difficult to predict the natural history of drug allergies. However, after a few years without exposure to treatments, the levels of antibodies responsible for the allergy or T lymphocytes can decrease or even disappear.
The problem, in this case, is the risk of resensitization: taking an antibiotic, in a true allergic situation, can be falsely reassuring when taken for the first time after a long-standing allergic episode. Indeed, even if nothing happens at the moment, it risks reactivating the immune memory, and thus triggering a new allergic reaction when the same antibiotic is subsequently taken.
It is therefore necessary, in order to have a complete allergological assessment, to test the patients again a few weeks after the possible reintroduction of the antibiotic, all on the specialist advice of an allergist.
What to do if you think you are allergic to an antibiotic?
In general, when you take a medication and you think you are suffering from an adverse effect related to this treatment, you must immediately notify your healthcare professional to find out whether you should stop said treatment. Alerted, he will also be able to initiate the necessary investigations to determine what type of adverse effect may be involved.
If your allergy to a family of antibiotics has been confirmed with certainty by a healthcare professional, you must ensure that they have mentioned it in your shared personal folder. Set up by the National Health Insurance Fund, this database allows all users of the French health system to store and keep their health documents and information up to date, and to make them accessible to caregivers.
In particular, it is necessary to ensure that all useful details are included, in particular the name of the responsible antibiotic, the nature of the allergy, other contraindicated medications, as well as alternative molecules. It is also prudent to keep a record of this information about you at all times, and to notify any new healthcare professional who takes care of you.
If you are in doubt about the certain nature of your allergy, you should discuss it as soon as possible with a healthcare professional, so that they can investigate (or refer you to the appropriate professional) to determine whether you are allergic or no, as well as the characteristics of this possible allergy and the practical consequences for the management of your health problems.
To guide its decision, it will be able to rely on the recommendations which have already been issued by certain countries (United Kingdom or Pays-Basfor example), or on European recommendations.
Of the French recommendations are also expected very soon, as indicated in the 2022-2025 national strategy for the prevention of infections and antibiotic resistance in human health.
Celine Pulcini is the author of the novel “ In the whirlwind of medicine »which notably addresses the subject of medical studies, infection prevention and antibiotic resistance.
Celine Pulciniprofessor of medicine, infectious disease specialist, university of Lorraine et Sébastien Lefèvreallergist, president of the national professional allergology council — head of department Regional Institute of Allergological, Environmental Pathologies and Clinical Immunology, Mercy Hospital (CHR Metz-Thionville), University of Lorraine
This article is republished from The Conversation sous licence Creative Commons. Lire l’article original.
Source: www.numerama.com
