Penicillin Allergy: Identification And Management
How to assess patients for true penicillin allergy and make appropriate treatment choices.
Hypersensitivity and allergy
Dr P Marazzi / Science Photo Library
In this article you will learn:
- The incidence of true penicillin allergy
- The drugs to avoid in patients with penicillin allergy
- How to manage patients who experience a severe allergic reaction to an antibiotic
All forms of natural and semisynthetic penicillins, or drugs with a similar structure such as cephalosporins or carbapenems, can cause allergy. These drugs, which have a beta-lactam ring, are recognised as one of the most frequent causes of immediate and non-immediate drug reactions,,. Adverse reactions to penicillin have been reported in 0.2% per course of treatment in a large unselected cohort, and between 3.35% in a large drug surveillance programme,.
However, a significant number of patients labelled as penicillin allergic are not truly allergic to the drug. As a result, these antibiotics can be withheld unnecessarily, which may subsequently affect their clinical outcomes, increase healthcare costs and contribute to the development of drug resistant bacteria.
Asmany as 85% of patients who previously reacted to penicillin may not react upon second exposure if the time interval from the last exposure is prolonged,.
What Causes An Amoxicillin Rash
While hives are most commonly caused by allergies, doctors arent sure what causes the maculopapular rash to develop.
If your child gets a skin rash without hives or other symptoms, it doesnt necessarily mean that they are allergic to amoxicillin. They may simply be reacting slightly to the amoxicillin without having a true allergy.
More girls than boys develop a rash in reaction to taking amoxicillin. Children who have mononucleosis and then take antibiotics may be more likely to get the rash.
In fact, the amoxicillin rash was first noticed in the 1960s in children who were being treated with ampicillin for mono, according to the Journal of Pediatrics.
The rash was reported to have developed in almost every child, between 80 and 100 percent of cases.
Today, far fewer children receive amoxicillin for mono because its an ineffective treatment, as mono is a viral illness. Still, about 30 percent of children with confirmed acute mono who are given amoxicillin will develop a rash.
Drug Reaction With Eosinophilia And Systemic Symptoms
This is a rare type of drug rash that can be life threatening. You may not notice symptoms of DRESS for 2 to 6 weeks after starting a new drug.
This type of rash looks red, often starting on the face and upper body. Additional symptoms are severe and can involve the internal organs, such as:
- fever
A drug rash or other reaction may occur for several reasons, such as:
- an allergic reaction
- a buildup of the drug that causes toxicity to the skin
- a drug makes the skin more sensitive to sunlight
- interaction of two or more drugs
In some cases, drug rashes can be idiopathic, meaning theres no known direct cause.
Your personal risk for developing a drug rash may be higher if you have certain risk factors, such as being older and being female.
You may also consider discussing other risk factors with your doctor:
- a viral infection and taking an antibiotic
- a weakened immune system due to an underlying condition or other drug
- cancer
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What Treatment Makes Contact Dermatitis Go Away Fast
The main treatment of contact dermatitis is to avoid the offending agent. However, treatments can make the contact dermatitis go away faster and provide relief from pain, itchiness, and rash and halt the progression of the condition.
- Moisturizers
- Applying moisturizer or emollient creams on the affected skin several times a day may be all that you need for mild contact dermatitis. The moisturizer helps seal the skin barrier and repairs the cracked skin.
- Even after the rash disappears, the regular application of moisturizing creams or lotions can form a protective barrier over the skin and prevent recurrent contact dermatitis.
Home remedies that you can try include:
- Application of cool compress
What Are The Signs And Symptoms Of An Allergic Reaction To An Antibiotic
- Mild symptoms include red, itchy, flaky, or swollen skin. You may have a flat, red area on your skin that is covered with small bumps. You may also have hives.
- Severe symptoms include skin that blisters or peels, vision problems, and severe swelling or itching. Severe reactions include conditions such as toxic epidermal necrolysis . Ask your healthcare provider for more information on TEN and other serious conditions.
- Anaphylaxis symptoms include throat tightness, trouble breathing, tingling, dizziness, and wheezing. Anaphylaxis is a sudden, life-threatening reaction that needs immediate treatment. Anaphylaxis may occur if you exercise after exposure to a trigger, such as after you take an antibiotic.
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What Puts You At Risk
Severe allergic reactions to penicillin can be dangerous and deadly. You may be more likely to have this type of reaction if you have had:
- A positive skin test for a penicillin allergy.
- Hives that appeared quickly after you took the penicillin.
- A bad reaction to penicillin in the past.
If any of these apply to you, you should receive another antibiotic or have desensitization therapy. In this type of therapy, you start taking small amounts of the penicillin and slowly increase how much you take. You do this under your doctor’s supervision. This lets your immune system “get used to” the medicine, and you may no longer have an allergic reaction. This process may have to be repeated if you have to use the antibiotic again in the future. This is because desensitization doesn’t last long.
You are not likely to have an anaphylactic reaction to penicillin if you have had a rash with red, blotchy spots that appeared from a few hours to days after you took penicillin.
How Do You Treat An Amoxicillin Rash
If your child develops hives, you can treat the reaction with over-the-counter Benadryl, following age-appropriate dosing instructions. Dont give your child any more antibiotics until a doctor sees your child.
If your child has a rash other than hives, you can also treat them with Benadryl if theyre itching. You should check with your doctor before giving any more of the antibiotic, just to rule out the chance of an allergic reaction.
Unfortunately, rashes are one of those symptoms that can be very confusing. A rash could mean nothing. Or, a rash could mean that your child is allergic to amoxicillin. Any allergy can be very serious quickly, and even put your child at risk for death.
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What Is A Penicillin Allergy
A penicillin allergy is a reaction by your immune system to the antibiotic drug penicillin. Since the 1940s, penicillin has been a go-to drug to clear up infections caused by bacteria. But some people get a bad reaction from taking it.
Your immune system is supposed to fight off the bacteria that make you sick. But sometimes your body fights the medicine itself. Thatâs what happens if you are allergic to penicillin. Your immune system thinks itâs an invader and wants to get rid of it.
Doctors try to match the right antibiotic to the right sickness. That job is tougher if you have a penicillin allergy. You may want to get tested if you notice problems.
Everything You Need To Know About Penicillin Allergies
Alexander Fleming first stumbled on penicillin as he grew bacteria in culture dishes in his London lab during September of 1928. Mold accidentally grew in the dishes and he noticed the mold had developed clear areas around itself where the bacteria could not grow. His discovery, and the subsequent scientific initiatives that allowed penicillin to be made widely available, is known as one of the greatest advancements in modern medicine.
Before the availability of penicillin, many bacterial infections were simply untreatable. People with life-threatening blood poisoning from a simple cut would be cared for in a hospital with little more than a wait and see approach. Today, penicillin comes in many forms and is still widely used to combat a range of bacterial infections. But in recent years, more and more patients have reported symptoms of penicillin allergies. In fact, according to the CDC, some 10% of patients in the U.S. report having had an allergic reaction to penicillin.
Read on as we explore how and why people develop allergies, proper identification, and what you can do to treat and prevent reactions.
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Is There A Downside To Avoiding Penicillin
Yes, says Dr. Lang. You may miss out on the most effective treatment for your condition.
Your doctor must find alternative antibiotics if you have a penicillin allergy. And alternative antibiotics often:
- Are more costly.
- Pose a greater risk for adverse effects.
- Are less effective.
A penicillin allergy needs to be challenged, he says. When we perform a formal allergy evaluation with penicillin skin testing, the results are negative in about every 9 out of 10 patients we evaluate. The negative skin testing implies that penicillin can be taken without an increased risk for allergic reaction compared with the general population.
Is Penicillin Allergy Common
Penicillin antibiotics are the most common cause of drug allergies. Some people who are allergic to penicillin are also allergic to other closely related antibiotics, including cephalosporins, such as cefprozil, cefuroxime, and cephalexin. Ask your pharmacist or doctor about these antibiotics.
Many people who believe that they have an allergy to penicillin do not. They currently may be less sensitive to penicillin than they were in the past. Or they may have had an adverse reaction, such as a side effect, rather than an allergic reaction. A skin test is the best way to find out whether you have a penicillin allergy.
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How Is An Allergic Reaction To Penicillin Treated
If your healthcare provider believes that your symptoms are caused by penicillin, he or she will likely advise you to stop taking it immediately and to take an antihistamine to help treat the symptoms of the allergic reaction. The provider may prescribe a corticosteroid to reduce inflammation or itching. Treatment with epinephrine may be necessary for severe reactions.
If the condition for which you started taking penicillin has not cleared up, your provider will most likely prescribe a different antibiotic. For most people, having an allergic reaction to penicillin does not mean that they will have a bad reaction to other antibiotics.
If you are diagnosed with a penicillin allergy, you should tell all of your providers, including your dentist and any specialists you see. Bring it up before undergoing any type of treatment or procedure. Describe your reaction to penicillin so the people caring for you are fully aware of your risk factors.
Penicillin Allergy: Symptoms Alternatives And Treatment
An allergic reaction to penicillin can be terrifying. While some people only experience mild effects like a rash or hives, some people suffer from a life-threatening allergic reaction called anaphylaxis. If you or a loved one are allergic to penicillin or you are worried that you might have a penicillin allergy, hereâs what you need to know.
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What Do Drug Rashes Look Like
Drug rashes are typically symmetric, meaning that they appear the same on both sides of your body.
Also, drug rashes dont tend to cause any other symptoms. However, some of these rashes may be accompanied by itching or tenderness.
If you develop a rash after starting a new drug, you may be suspicious that your medication is causing this skin reaction. This rash may develop suddenly or within hours, but it can take up to several weeks in some cases. You might also notice that the rash disappears once you stop taking the drug in question.
Take a look at some of the most common types of drug rashes below:
What Is A Medication Allergy
A true allergic reaction to medication occurs when the immune system is activated in response to a drug. The medication can be taken by mouth, injected into the body or rubbed on the skin. The symptoms from an allergic reaction vary from a mild skin rash to sudden swelling of many body parts with life threatening fall in blood pressure.
Most people with a drug allergy have been exposed to that drug or a similar drug before. During the earlier exposure, immune cells formed antibodies against the drug. Antibodies are proteins created by the immune system to battle foreign invaders such as bacteria and viruses. When a person is exposed to the drug again, the antibodies go into action, setting off the allergic response. The symptoms of drug allergy may happen immediately or after taking the drug for a week or more.
The reason a person develops a particular drug allergy is usually unknown, but genetics probably play a significant role.
Drug allergies can pose a significant problem, not only because of the symptoms they cause, but also because they can prevent or hinder the use of the more effective medications to treat medical conditions.
For many, medication allergies go undetected until they take a drug and have an allergic reaction.
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What Are Drug Rashes
Drug rashes are the body’s reaction to a certain medicine. The type of rash that happens depends on the medicine causing it and your response. Medicines have been linked to every type of rash, ranging from mild to life-threatening. The timing of the rash can also vary. It may appear right away or a few weeks after you first take the medicine.
Rashes caused by medicines can be put into one of 3 groups:
-
Rashes caused by an allergic reaction to the medicine
-
Rashes as an unwanted side effect of a certain medicine
-
Rashes from extreme sensitivity to sunlight caused by the medicine
How Long Does It Take A Rash Due To A Penicillin Allergy To Clear
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What Other Precautions Should I Consider If I Have A Penicillin Allergy
Ask your healthcare provider if your penicillin allergy is severe enough for you to wear a medical alert bracelet warning others about it. If so, they can advise you on how to get one.
In the rare cases in which there is no other antibiotic that is a safe and effective alternative, a physician may recommend drug desensitization therapy. In this therapy, you take a small amount of the drug, and then gradually take more until you are able to take the recommended dose without having side effects. This may be done in a hospital so that expert care is available if there is a serious problem. The effects of desensitization therapy may not be permanent some patients may need to go through it again later in life.
When To Call A Professional
Symptoms of an acute severe allergic reaction such as rapid pulse, labored breathing and facial swelling require an immediate visit to an emergency care facility. Other reactions should be reported promptly to your physician so that your treatment can be evaluated and you can avoid the medication that caused the reaction.
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What Steps Do I Need To Take For Signs Or Symptoms Of Anaphylaxis
- Immediately give 1 shot of epinephrine only into the outer thigh muscle.
- Leave the shot in place as directed. Your healthcare provider may recommend you leave it in place for up to 10 seconds before you remove it. This helps make sure all of the epinephrine is delivered.
- even if the shot improved symptoms. Do not drive yourself. Bring the used epinephrine shot with you.
What Does Penicillin Allergy Testing Entail
An allergist can assist in the diagnosis of a penicillin allergy using a skin test. This test involves pricking the skin, usually on the back or on the inside of the forearm, and placing a small amount of allergen on the punctured skin. The allergist will compare how your skin reacts to penicillin versus a positive control and a negative control . Anyone with a positive skin test to penicillin theres usually itching, redness, and swelling at the site of the skin prick is allergic and should avoid penicillin.
People who have no reaction to the skin test can safely undergo the amoxicillin challenge. In this test, the allergist gives the person amoxicillin and observes signs and symptoms for at least one hour. This is done under medical supervision.
Although these tests are very useful for diagnosing penicillin allergies that are immediate, there are other types of allergies that may still occur. The most common is a minor drug rash that happens days into the course of antibiotic treatment.
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