Our Symptom checker provides clinical advice on what to do next based on your symptoms.
Allergic reactions to antibiotics
Some people have an allergic reaction to antibiotics. Learn about the symptoms and the difference between allergic reactions and side effects.
Antibiotics revolutionised medicine in the 1940s because they treated infections caused by bacteria. Learn how antibiotics work.
Penicillin is the name given to a widely-used group of antibiotic drugs. Penicillin can have side-effects, and some people suffer allergic reactions. Find out more here.
Doxycycline is an antibiotic medicine. This page explains what doxycycline is used for, how it works, its risks and other treatment options available in its place.
Cefalexin is used to treat bacterial infections in various parts of the body. This page explains how cefalexin works, its risks and other treatment options available in its place.
Trusted information about allergy types, as well as allergy testing, anaphylaxis, antihistamines and common related conditions such as asthma and hay fever.
Cat and dog allergy
Allergies to cats and dogs are common, and symptoms can be severe. Learn more about how to live with a pet allergy.
Grass allergy causes someone to have an allergic reaction to grass pollen spread by the wind. Learn more about its symptoms, diagnosis and treatment.
Allergies and hypersensitivities
An allergic reaction occurs when the immune system overreacts to a foreign substance that usually causes few or no problems in most people.
Here’s important information about what antibiotics treat and don’t treat, an explanation of 'superbugs' and how antibiotic resistance can be reduced.