Most people must have heard about ‘Drug allergy’. However, many of them do not know what exactly it is & what to do if someone has got drug allergy. In this post, the subject has been made as simple as possible to understand by anyone. Let’s dive into the post!
What is a drug allergy?
A drug allergy is an unwanted reaction to a medicine or drug that is being used for treatment purposes. This unwanted reaction happens when the body’s defense system (immune system) responds to a drug as if it were a harmful object to the body and tries to fight it off. This is also called “drug hypersensitivity.”
Can you explain hypersensitivity in a little detail?
Naturally, we have a defense system, in our body, to fight off any infection or other harmful object that enter our body. This system is called the immune system. The immune system is highly skilled in attacking and neutralizing the harmful intruders.
Normally, it should not react to a drug as though it were an invader, but some drugs can cause that response in some people. The immune system mistakenly react and responds, and in doing so symptoms appear which is called ‘drug allergy.’
In other words, a drug allergy is an unwanted reaction to a medicine or drug that is being used for treatment purposes.
What are the symptoms of a drug allergy?
The symptoms can include a skin rash, itching, and swelling. In severe cases, drug allergy can also cause trouble breathing or a drop in blood pressure that can cause a person to pass out. Let me dive into a bit of detail here.
There are a few different types of drug allergies. Each has its own set of symptoms.
One serious type of allergy is called an “immediate” allergy because it starts quickly after a drug is taken (usually within an hour or so). It usually happens with drugs that a person had taken before without any problem. Symptoms can include:
- Hives, which are raised patches of skin that are usually very itchy
- Itchy skin
- Flushing, which is when your skin turns red and feels hot
- Swelling of the face, hands, feet, or throat
- Throat tightness, hoarse voice, wheezing, or trouble breathing
- Nausea, vomiting, belly pain
- Feeling lightheaded
This type of allergy is serious because it can get worse if you keep taking the drug. It can turn into a life-threatening, whole-body allergic reaction, called anaphylaxis.
Another type of drug allergy, called a “delayed” allergy, is much more common. This type is not very serious and usually causes a rash that begins after a few days of taking a drug. The rash often spreads over much of the skin. Sometimes it is itchy, but sometimes not. This type of drug allergy does not involve swelling, trouble breathing, throat tightness, or the other symptoms mentioned above. This type of allergy doesn’t usually get worse or affect anything besides the skin. It shall be noted, however, a severe, but rare, skin reaction to a drug, called Stevens-Johnson syndrome, is different and requires immediate medical attention.
So can we call drug allergy a drug side effect?
A drug allergy is not the same as a drug side effect.
Side effects are unintended or unwanted effects that drugs can cause. Side effects can affect anyone who is given enough of a drug.
Drug allergies, on the other hand, affect only a small number of people.
When should I see a doctor?
See a doctor immediately, if you start a new medicine and develop any of these symptoms:
- Swelling of your face, lips, tongue, or throat
- Chest tightness or pain
- Wheezing or trouble breathing
- Passing out or feeling like you might pass out
When should I call a doctor?
Call your doctor if you start a new medicine and develop any of these symptoms:
- Hives (raised patches of skin that are usually very itchy)
- Feeling like you want to hurt or kill yourself
- Severe stomach ache or vomiting
- High fever
- Painful skin
- Skin blisters
- Pain and irritation of the pink, moist tissue that lines the eyes, mouth, vagina, and other organs
How is a drug allergy treated?
If there is a severe reaction to a drug, it will be treated in a hospital. There, the healthcare team will try to get things back to normal by giving some medicines to calm down the body’s allergic response.
After the symptoms are managed first, the doctor will explore what to do about the allergy. If possible, the doctor might try to switch to a different drug that is less likely to cause the same reaction. If that is not possible, they might send the patient to an allergist (allergy doctor) to decide what to do next.
Any tests are done on drug allergies?
Maybe. If the allergist suspects you have an immediate drug allergy, they might do allergy tests. The most common type of testing is called allergy skin testing. For this test, the doctor puts a drop of the drug you might be allergic to on your skin and makes a tiny prick in your skin, or injects a very tiny amount. Then they watch your skin to see if it turns red or bumpy.
If you have a reaction that consists only of a rash (the type that is not serious), your allergist might want to do a “drug challenge test.” For this test, the allergist will have you take a small amount of the drug that caused the rash while they observe you. That way the doctor can find out if you will have the same reaction twice. Doctors usually do drug challenge tests only with certain medicines that are used a lot and can’t easily be replaced with a different medicine. For example, the antibiotic amoxicillin is the best choice of antibiotic for many common infections. Because of this, it’s important that people only avoid it if they are truly allergic.
Can drug allergies be prevented?
If you already know you have a drug allergy, you can reduce your chances of having problems again if you:
Inform all your doctors and anyone who might prescribe medicines for you, about your allergy. Tell your pharmacy, too. Medicines sometimes have more than one ingredient and go by more than one name, so it won’t always be obvious if you are being prescribed the problem drug.
Also, drugs are sometimes related to each other. If you are allergic to a specific drug, you might also be allergic to others that are related to it. If you tell your doctor about your allergy, they can try to avoid giving you any drugs that could cause problems.
Wear a medical alert bracelet or necklace explaining your drug allergy.
