Asthma Attack vs Chest Infection
By the AllHealth UK editorial teamLast reviewed Next review due Compiled from published NHS and NICE guidance. Not reviewed by a clinician.
Is it an asthma attack or a chest infection?
An asthma attack is your airways narrowing: wheeze, chest tightness and breathlessness that build over minutes to hours, usually without a fever. A chest infection builds over days with a chesty cough, green or yellow mucus and a high temperature. An infection can trigger an attack, so you can have both. If a reliever inhaler is not working, call 999.
Immediate action required: call 999 or go to A&E if
- You are having an asthma attack and start to feel worse at any time
- You do not feel better after taking the maximum dose from your reliever inhaler
- You are having an asthma attack and do not have an inhaler with you
- You are too breathless to speak in short sentences while resting
If you are weighing up whether it is bad enough to call, that is itself a reason to call. Nobody is annoyed by a 999 call that turns out to be the less serious of the two.
| Feature | Asthma Attack | Chest Infection |
|---|---|---|
| Typical signs |
|
|
| How long it lasts | Minutes to hours — does not settle without treatment | Usually better in 7–10 days; cough and mucus can last up to 3 weeks |
| What helps | Sit up straight, stay calm, use your reliever inhaler as your asthma action plan says. Call 999 if you feel worse or the maximum dose has not helped | Rest, fluids, painkillers. A pharmacist can suggest a cough medicine. Antibiotics only help if a GP finds it is bacterial |
| What to do | Call 999 now | Self-care at home |
Sources and further reading
This page was written from the following published guidance. All links checked 26 August 2026.
What to do next
Not sure whether this needs a doctor? These are your options, cheapest and fastest first.