Is it an antibiotic allergy or a side effect?

While antibiotic allergies are uncommon, they represent substantial obstacles in patient treatment. Differentiating between true allergies and side effects is critical for selecting the best treatment and avoiding bad reactions, writes Dr Bindumathi P L

Antibiotics have transformed our ability to fight bacterial illnesses. Antibiotic allergies, which can vary from moderate skin reactions to life-threatening anaphylaxis, have been raised as a result of their widespread use. The capacity to differentiate between actual antibiotic allergies and side effects is critical for selecting the best treatment and ensuring patient safety.

Understanding antibiotic allergies

A true antibiotic allergy is an immunological reaction to an antibiotic in which the body’s immune system misidentifies the antibiotic as a potentially hazardous agent and mounts an excessive response. This reaction can present itself in a variety of ways, including:

Acute mild reactions: The most common symptoms are skin responses, which can range from a milder form of a rash, itching edema of the face, lips, and then whole body, or vomiting, and mild breathlessness.

Severe reactions: Respiratory problems might include severe breathlessness, and progress to severe form with hypotension anaphylaxis, Steven-Johnson syndrome, severe mucocutaneous involvement, and other systemic organs. It can also involve reactions like liver and kidney failure in isolation or with other organs.

Chronic reactions: This can involve immune-mediated chronic skin conditions like eczema, serum sickness like fever, rash, and joint pain. It could also harm organs like the liver or kidney, chronic skin involvement and photosensitivity.

Antibiotics are to be used under clinical supervision only and carefully. Drug interactions may also be there if taken alongside other medicines. While prescribing antibiotics, it is required to know the side effects and drug interactions. If there have been previous allergies, it is supposed to be used with caution.

Antibiotic side effects

Antibiotic side effects, on the other hand, are non-immunological reactions generated by the antibiotic’s pharmacological properties. They are usually milder than real allergies and may include:

Problems with the gastrointestinal tract: Certain antibiotics are known to cause nausea, vomiting, diarrhoea, and stomach discomfort.

Post antibiotics, the body can produce severe clostridium difficile infections which is an antibiotic-induced diarrhoea. Antibiotics can also induce other infections, like fungal infections. It can affect organs like the kidney, liver, eyes, and sometimes, nerves as well.

Side effects could also occur due to genetic defects, like hemolysis in G6P deficiency etc.

Misconceptions surrounding antibiotic allergies

With its diversified population and diverse healthcare ecosystem, India has distinct antibiotic usage challenges. The prevalence of infectious infections, combined with the broad availability of antibiotics, highlights the importance of a comprehensive study of antibiotic allergies. In the context of India where self-medication is popular, the possibility of misconceptions and overreporting of allergies increases. One widespread misperception is that antibiotic allergies are more common than they are. Antibiotic allergy overreporting can result in unwarranted drug avoidance, restricting treatment options and raising the risk of antibiotic resistance. The following factors contribute to this misconception:

Confusion of side effects and allergies: Patients may confuse common side effects, such as rash or stomach trouble, as symptoms of an allergy.

Previous adverse drug reactions: Patients may correlate previous adverse drug reactions, not necessarily to antibiotics, with an antibiotic allergy. Healthcare providers can help dispel myths and educate patients about antibiotic allergies. Open communication and comprehensive patient education can assist in distinguishing between allergies and side effects, guaranteeing accurate reporting and appropriate treatment decisions.

Diagnostic approaches

Accurate antibiotic allergy identification is critical for directing therapy and preventing future responses. Allergy testing can establish the presence of a real allergy and assist in determining which antibiotic is to blame.

There are two main approaches:

Skin tests: Skin testing entails applying small doses of several antibiotics to the skin and observing the reaction.
Blood tests: These assess the amount of particular antibodies known as IgE antibodies, which indicate an allergic reaction. For example, G6P deficiency and genetic studies.

Despite breakthroughs in diagnostic procedures, reliably detecting antibiotic allergies remains difficult. Cross-reactivity, which occurs when an allergy to one antibiotic causes reactions to other antibiotics, might make diagnosis more difficult. Furthermore, false-positive results might occur as a result of underlying skin problems or prior exposure to related drugs.

Treatment strategies

Managing antibiotic allergies and dealing with side effects necessitates several approaches:

True antibiotic allergies: It is critical to avoid the offending antibiotic. To reduce the possibility of cross-reactivity, other antibiotics with different chemical structures can be chosen.

Antibiotic side effects: Symptomatic relief is frequently adequate. Probiotics may help restore gut flora balance in people suffering from gastrointestinal disorders. Topical antihistamines or corticosteroids can be used to treat skin responses. Avoiding sun exposure and wearing protective gear and sunscreen can help to reduce photosensitivity.

In severe reactions like life-threatening conditions, these allergies or side effects have to be treated as per the doctor’s advice.

Genetic studies to give antibiotics and the responders will be the future research.

(The author is a senior consultant in internal medicine.)