Medication and Drug Allergies
Adverse reactions to medications are common. Allergic reactions to medications are a type of adverse reaction, specifically an IGE mediated immune response. The providers at Impact Medical can help diagnose whether you are truly allergic to a medication.
What Are Medication & Drug Allergies?
Medication allergies occur because of an immune response to a particular medication. Medications can produce a variety of immune responses leading to different types of reactions. Drug allergies can potentially be life-threatening and need to be diagnosed correctly.
Common Medication Allergies and Drug Allergic Reactions
Penicillin Allergy
Penicillin allergy is the most common medication allergy; however, 80% of patients who report a penicillin allergy are actually not allergic. It is extremely important to have the correct diagnosis, as penicillin is one of the most effective and safest families of antibiotics. Patients who are misdiagnosed are often placed on other antibiotics that are less effective or have significant side effects.
If you have a history of a suspected penicillin allergy, the doctors at Impact Medical will evaluate you via a thorough history, a blood test called ImmunoCAP testing, and standardized penicillin skin testing.
If diagnostic testing for penicillin is negative, we will then have the patient undergo a cautious graded challenge to a penicillin (or a derivative) in the office. This consists of exposing the patient to penicillin via increasing doses until a full dose is received. Patients are examined and vital signs are checked every 15-20 minutes. The entire procedure typically is performed over 2 hours. A cautious graded drug challenge can also be performed on other types of medications, such as azithromycin, ciprofloxacin, acetaminophen, etc, in which diagnostic testing is not available.
NSAID Allergy
NSAIDs (non-steroidal anti-inflammatory drugs) can cause a variety of reactions. NSAIDs include medications such as aspirin, ibuprofen (aka Motrin or Advil), naproxen, and many more. People with an allergy to NSAIDs can present with an increase in their asthma symptoms, hives, swelling, or a severe allergic reaction. An allergy to NSAIDs is diagnosed based on history as there is no specific skin or laboratory test to confirm the diagnosis. Typically, if a patient is allergic to one NSAID, they need to avoid the entire family of NSAIDs.
What Are Symptoms of a Medication Allergy?
Medication allergies can manifest in a variety of ways. Some of the most common symptoms include:
Rash or Hives
Raised, itchy, red patches on the skin or welts that can appear suddenly after taking a medication
Swelling
Swelling or edema can occur in specific parts of the body, like the face, lips, or tongue, or it can be more generalized
Itching
A general or localized sensation of discomfort and the urge to scratch, which may or may not be accompanied by visible skin changes
Fever
An elevated body temperature may accompany an allergic reaction to medication
Upset Stomach
This can include symptoms like nausea, vomiting, diarrhea, or abdominal cramps because of the body’s adverse reaction to a drug
Shortness of Breath
Difficulty breathing, often due to the inflammation or narrowing of airways, sometimes leading to wheezing
Runny Nose or Watery Eyes
Similar to the reaction experienced with environmental allergies, some medications can cause an overproduction of mucus or tears
Dizziness or Lightheadedness
A feeling of unsteadiness or near-fainting, which could be due to the body’s response to the medication or a decrease in blood pressure
Joint Pain
Some allergic reactions to medications can manifest as joint pain or even resemble arthritic symptoms
Anaphylaxis
A severe, potentially life-threatening allergic reaction that can occur rapidly. Symptoms may include difficulty breathing, a rapid or irregular heartbeat, confusion, nausea, or a drop in blood pressure
Diagnosing & Treating Drug Allergies
Medical History & Evaluation
Your allergist will begin by gathering a comprehensive medical history and performing a physical exam.
Diagnostic Testing
ImmunoCAP laboratory testing, allergy skin testing and cautious graded challenges will be recommended if indicated to confirm if one is or is not allergic to a medication.
Treatment
If one is diagnosed with a medication allergy, your allergist will develop a treatment plan with a focus on avoidance.
Drug Allergy Diagnostic Testing
How to Treat a Medication Allergic Reaction
Medication & Drug Allergies FAQs
For the majority of medications, diagnostic testing is not available. Penicillin is one of the few medications for which we have standardized diagnostic testing. However, even if there is no testing available for a medication, your allergist at Impact Medical will take a detailed history and determine if it is safe to perform a cautious graded challenge to rule in or rule out a medication allergy.
Yes, outgrowing medication allergies is possible. For example, 10% of patients per year outgrow a penicillin allergy for eight years, with 20% of patients having a persistent penicillin allergy.
There is a mold called penicillium which naturally produces penicillin. If one is allergic to the mold penicillium it does not indicate a penicillin allergy.
Typically, we do not recommend taking cephalosporin if one is allergic to penicillin. Penicillin and cephalosporins both share a common structure called a Beta Lactam ring – which increases their allergic cross-reactivity. If one is allergic to penicillin, there is a 5 – 15% likelihood they will be allergic to cephalosporin.
Yes, it is possible but unlikely to be allergic to cephalosporin if you are not allergic to penicillin.
Yes. Tylenol (acetaminophen) is not in the NSAID family.
RCM contains Iodine. This is what patients react to in RCM. Iodine is often present in shellfish. Iodine sensitivity can lead to an anaphylactoid reaction, which is a non-IGE mediated response. This is not a true allergic reaction. However, patients with an iodine sensitivity can develop symptoms that mimic an allergic reaction with exposure to RCM and shellfish. Therefore, patients who are allergic to RCM should consult with an allergist at Impact Medical before eating shellfish.
This is a very common question we come across at Impact Medical. One will require a full evaluation to determine if a rash is from a medication or from the infection itself.
There are certain components of vaccines that can be tested for. For example, the MMR vaccine contains porcine gelatin which is a known allergen. Patients can be tested for an allergy to porcine gelatin.
