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Plain-language information for patients

What is sepsis?

Sepsis is a life-threatening emergency that happens when the body's response to an infection injures its own tissues and organs. It needs urgent treatment — every hour counts.

When to get help immediately

Call 999 or go to A&E if an adult or child with a likely infection has any of: slurred speech or confusion, extreme shivering or muscle pain, passing no urine in a day, severe breathlessness, a rash that does not fade when pressed, or skin that is mottled, very pale or blue. In a child, also act on fast breathing, a fit/convulsion, or a child who is much sleepier or floppier than usual.

If you are worried that you or someone else might have sepsis, say so — ask directly: 'could this be sepsis?'

Why sepsis is so serious

Any infection — a chest infection, urine infection, skin infection or wound — can occasionally trigger sepsis. The immune response becomes overwhelming and can lead to a dangerous drop in blood pressure and organ failure.

In hospital, treatment is rapid: oxygen, fluids, blood tests including lactate, and antibiotics, often within the first hour. Early recognition saves lives.

Common questions

Who is most at risk of sepsis?

Very young babies, older people, those with weakened immune systems or long-term conditions, and people who have recently had surgery are at higher risk — but sepsis can affect anyone with an infection.

Related tools

These calculators are designed for healthcare professionals.

This page is general information, not personal medical advice, and does not replace a consultation with a qualified health professional. If you are worried about your health, please speak to your GP, pharmacist, or another clinician. Last reviewed 2026-06-09.