Allergy medicines explained: antihistamines, nasal sprays and adrenaline

Everyday allergy relief: antihistamines

Most everyday allergy symptoms — sneezing, an itchy or runny nose, itchy eyes and hives — are driven by a chemical called histamine that your body releases in response to an allergen such as pollen, dust or pet dander. Antihistamines block its effects and so calm these symptoms. Modern, non-drowsy antihistamines such as cetirizine are usually preferred for daytime use because they are far less likely to make you sleepy than older types. They can be taken when symptoms strike or, for predictable triggers like the hay fever season, regularly to keep symptoms at bay. They are widely available and generally very safe, though it is still worth checking with a pharmacist if you take other medicines or have other health conditions.

Steroid nasal sprays for hay fever — and technique

For a blocked, runny or congested nose, especially in hay fever, a steroid nasal spray (a nasal corticosteroid) is often the most effective treatment. It calms inflammation in the lining of the nose, easing congestion that antihistamines alone may not fully clear. The catch is that it works best taken regularly through the season rather than only on bad days, and it can take a few days to build its full effect, so persistence pays off. Technique matters: gently clear your nose first, aim the spray slightly outward toward the side of the nostril rather than straight up at the central wall, and breathe in gently without sniffing hard. Good technique reduces irritation and gets the medicine where it works.

Everyday allergy versus anaphylaxis

It is vital to tell ordinary allergy apart from anaphylaxis, a severe whole-body reaction that is a medical emergency. Everyday allergy causes bothersome but limited symptoms — sneezing, itching, a rash or watery eyes. Anaphylaxis is different and far more serious: it can cause swelling of the lips, tongue or throat, difficulty or noisy breathing, a tight chest, a sudden widespread rash, feeling faint or collapsing, often coming on quickly after a trigger such as a food, insect sting or medicine. Antihistamines are not a treatment for anaphylaxis — they are too slow and too weak for a reaction of this severity. Recognising the difference, and acting fast, is what keeps someone safe.

Adrenaline auto-injectors: the emergency treatment

Adrenaline is the only emergency treatment for anaphylaxis, and adrenaline auto-injectors deliver it quickly into the outer thigh — they are designed to be used through clothing in an emergency, even by someone with no medical training. If you suspect anaphylaxis, use the injector without delay and call 999 immediately, telling them it is anaphylaxis; lay the person flat with their legs raised (or sit them up if breathing is hard). Always carry two auto-injectors, because a second may be needed if symptoms do not improve, and a reaction can return after seeming to settle. Check the expiry date and the medicine's appearance regularly, replace before it runs out, and make sure family, friends or school know where it is and how to use it.