High temperature in an adult: what to know

Fever can develop when the immune system responds to an infection or inflammation. The temperature reading matters, but so do the person's breathing, alertness, hydration, pain, and other symptoms. A cold, COVID-19, acute bronchitis, or another infection can be associated with fever. A localised painful, red, hot area of skin may point towards cellulitis, while a widespread itchy blistering rash may occur with chickenpox. A fever does not identify its cause by itself.

Chills, sweating, headache, muscle aches, tiredness, and a reduced appetite can accompany fever. The illness may improve as the underlying problem settles, but worsening symptoms or difficulty keeping fluids down deserve advice.

Rest, drink regularly, wear light clothing, and keep the room comfortably ventilated. Check your temperature in a consistent way and note when symptoms began. If you use paracetamol or another fever-relieving medicine, follow the label and check with a pharmacist if you have liver or kidney disease, take other medicines, or drink heavily. Avoid taking extra products that contain the same ingredient. Antibiotics do not treat viral illnesses, so treatment depends on the cause.

Get urgent help for trouble breathing, chest pain, fainting, new confusion, a seizure, a stiff neck, a severe headache, or a rash that does not fade when pressed. Seek same-day medical advice if you are becoming dehydrated, have persistent vomiting, severe localised pain, or a weakened immune system. Arrange a clinical review if the fever is worsening, keeps returning, or does not begin to settle, especially after travel or possible exposure to an unusual infection.

Ask what the pattern of fever and accompanying symptoms suggests, whether you need an examination or tests, which medicines are suitable for you, and how long to monitor before contacting the practice again.