Understanding symptomsDrug allergyand its different types
Sometimes, you might think that when you developa mouth sore ordiarrhea during treatment withor after taking antibiotics, you are allergic to the medicine. However, these symptoms are actually side effects caused by changes in bacterial flora.It’s unclear why some people are allergic to certain medicines while others are not. In fact, allergic reactions to drugs do not happen often and rarely occur on the first use.
Additionally, if you are undergoing testing to confirm whether you have a drug
allergyor not, it’s unnecessary to repeat the test regularly. If you want to learn more about this issue, keep reading. In this section of SelMagz health and wellness, we will explain these allergies in more detail.What is a drug allergy or drug hypersensitivity?
When your immune system mistakenly identifies a drug as a harmful substance, like a virus or bacteria, a drug allergy occurs. When the immune system recognizes a drug as harmful,
an antibodyis produced specifically for that drug, which can happen even on the first use of the drug. However, sometimes allergy does not develop until repeated exposure.During subsequent use, these specific antibodies target the drug, triggering an immune response. The chemicals released during this process cause symptoms related to allergic reactions. However, you may not notice the allergy from the very first exposure.
Some evidence suggests that even small amounts of a drug present in foods, like antibiotics, might be enough for the immune system to create antibodies. Allergic reactions can also result from different processes.
Researchers believe certain drugs can directly bind to a specific type of immune cell called T lymphocytes. This event can cause the release of chemicals that might trigger an allergic response on the first dose.
Some individuals may have allergic reactions to medicines. People over 40 are at higher risk of drug allergies, which is related to aging and exposure to certain drugs or substances earlier in life.
Symptoms of allergic reactions and drug hypersensitivity
Severe allergic reactions usually occur within an hour of taking the medication. Some symptoms include:
Intense skin itching
- Hives
- Skin rashes
- Fever
- Swelling and inflammation
- Shortness of breath
- Coughing
- Runny nose
- Watery and itchy eyes
- Medications that cause allergies
While any medicine can potentially trigger an allergic reaction, some drugs are more commonly linked to allergies, including:
Antibiotics, such as penicillin
- Pain relievers, like aspirin, ibuprofen (Advil, Motrin IB), and
- NaproxenSodium (Aleve)Chemotherapy drugs
- used for cancer treatmentand medications for autoimmune diseases, such as rheumatoid arthritisHow to recognize allergic reactions to medicines?
- When you take a medicine and are allergic to it, the symptoms can vary. Allergic reactions can be immediate or delayed. It’s best to stop taking the medication as soon as allergy symptoms appear.
1- Immediate Reaction
This type of reaction happens right after taking the medicine. It usually occurs when you take your first or second dose, within half an hour to an hour. Common symptoms include skin reactions like
hives
and swelling of the lips and eyes. Serious reactions such as anaphylaxis can also occur.Symptoms and signs of anaphylaxisIn previous health and wellness sections of SelMagz
you read that some signs of anaphylaxis include:
Swelling of the airways and throat that causes breathing problemsNausea or stomach crampsVomiting or diarrhea
- Dizziness or fainting
- Weak or rapid pulse
- Seizures
- Low blood pressure
- Loss of consciousness
- Other allergic conditions caused by drugs
- Serum sickness, which may cause fever, joint pain, rashes, swelling, and
- Nausea
Drug-induced anemia, a reduction in red blood cells leading to fatigue,
- rapid or irregular heartbeat,shortness of breath,and other symptoms
- Drug eruptions with eosinophilia and systemic symptoms (DRESS), leading to rashes, low white blood cell count, widespread swelling,lymph node swellingand recurrent infectionsHepatitisand other serious conditions
- that require medical attentionWhen to see a doctor?If you notice severe or suspicious signs of anaphylaxis after taking a medication, call emergency services immediately.2- Delayed ReactionsDelayed reactions usually affect the skin. The most common one is a rash that may appear up to two weeks after taking the medication. It’s characterized by a pinkish color and itching, spreading to different parts of the body.
- This type of reaction is less common but more severe, and may cause skin burns. In such cases, hospitalization might be necessary due to the risk of death.
Can a medicine cause other types of reactions?
Other than predictable and unpredictable reactions are classified into two categories: expected and unexpected, each with their own reasons which are explained below.
Predicted Reaction
Expected reactions, or Type A, have the most allergenic effects. They result from the medicine you took and can occur due to factors such as:
Overdose or toxicity of the drug
Side effects of the drug
Interactions with other medicines
Generally, reducing the dose will eliminate symptoms, and you can safely continue using the medication if needed.
Unpredictable Reaction
- Another type of reaction is called unpredictable or Type B. These reactions are related to drug intolerance or pseudo-allergic responses. Drugs most commonly associated with this type of allergy include:
- Aspirin
- Contrast media used in imaging tests (radio-contrast media)
Opioids used for pain relief
Local anesthetics
Pseudo-allergic reactions involve symptoms similar to allergy but do not have an immunological basis.
- Factors increasing the risk of drug allergy include:
- While anyone can have an allergic reaction to a certain medication, certain factors may increase the risk, such as:
- History of other allergies like
- food allergies
or hay fever
Personal or family history of drug allergies
Higher doses or prolonged use of the medication
- Some illnesses related to drug allergic reactions include:Infection with HIVor Epstein-Barr virus
- How to prevent drug allergies?
- If you have a drug allergy, the best approach is to avoid the problematic medication. Steps to protect yourself include:
- Inform healthcare providers.Make sure your medical records clearly state your drug allergies.Notify other healthcare providers, like dentists or specialists.
Wear a medical alert bracelet indicating your drug allergies. This information can help in providing proper treatment during emergencies.
What to do in case of an allergic reaction to medication?
- Once a drug allergy is confirmed, immediate steps should be taken to treat the symptoms. The treatment depends on whether the reaction is immediate or delayed.
- For immediate reactions, medications like adrenaline, corticosteroids, and
- antihistamines are used. Additionally, medicines to treat affected organs, such as bronchodilators and cardiotonics, may also be administered.
- For delayed or non-immediate reactions, corticosteroids form the main treatment. The specific medication depends on the symptoms—local treatments are used for contact dermatitis, for example.
Drug allergy
causes and reasons for drug allergy
Drug allergyand its causesinclude
intense skin itching
