The truth is, while a true drug allergy is serious, many reactions people experience are actually common side effects. Knowing the difference is crucial for your health.
Here is a guide from your local North East pharmacy team to help you understand what might be happening, and when you need to act fast.
The most important thing to understand is how your body reacts:
A Side Effect (or 'Intolerance') is a known, expected complication of a drug that is listed on the patient information leaflet. It is a chemical reaction caused by the medicine itself and does not involve your immune system. Examples include nausea, dizziness, mild headache, or dry mouth. Side effects are often unpleasant but are rarely life-threatening, and they sometimes improve as your body adjusts to the medication.
A True Drug Allergy is a rare but serious reaction involving your immune system. Your body mistakenly identifies the medicine as a threat (like a virus) and releases chemicals, such as histamine, to fight it off. This reaction can be more severe the next time you take the drug.
Allergic reactions usually occur rapidly—within minutes to a few hours of taking the medicine—though some can be delayed by days or weeks.
Look out for these classic signs of an allergic reaction:
Skin Reactions: An itchy, raised, blotchy rash (hives or nettle rash), or widespread redness and swelling.
Swelling: Swelling of the lips, face, tongue, or throat (Angioedema).
Respiratory Problems: Shortness of breath, wheezing, coughing, or tightness in the chest.
If you experience sudden, severe symptoms—such as difficulty breathing, a feeling of throat tightness, wheezing, severe dizziness, or fainting—this could be anaphylaxis, a life-threatening allergic reaction. Call 999 immediately.
If your symptoms are mild (like a small rash or slight nausea), stop taking the medicine immediately and follow this advice:
Contact Riverview HC Pharmacy First: Don't wait for a GP appointment. Our experienced pharmacists at both our branches are a quick and trusted source of advice. Tell us exactly what medicine you took and what symptoms you are experiencing. We can assess your symptoms and advise whether it's a mild side effect, a potential allergy, or if you need to contact your GP or NHS 111.
Antihistamines (OTC): For mild allergic symptoms like an itchy rash or hives, a pharmacist may recommend an over-the-counter non-drowsy antihistamine (like Cetirizine or Loratadine) to ease the symptoms. However, always check with our pharmacist first before taking any new medication, even an antihistamine.
Record the Details: Make a note of the drug's name, the dose, when you took it, and exactly what your symptoms were. This information is vital for your medical records.
Inform Your GP: You must let your GP know about the suspected allergy so they can permanently mark it on your record and ensure you are only prescribed safe alternatives in the future.
Whether you are starting a new course of antibiotics or simply concerned about an ongoing side effect from a long-term prescription, your team at Riverview HC Pharmacy is here for you. We provide essential and trusted medical guidance for the North East community, helping you distinguish between a harmless side effect and a reaction that needs immediate attention.
Visit us today—we are always available to offer a confidential consultation.
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