Autumn Asthma: Why Your Asthma Gets Worse in Autumn — and How to Manage It
Why asthma often flares in autumn: mould spores, back-to-school colds, cold air and changeable weather, the September rise in attacks, and how to get ahead with your preventer, flu jab and action plan.
Part of our asthma guide: symptoms, triggers and treatment.
Asthma attack? Get help now. Call 999 if your reliever isn’t helping, you’re too breathless to speak, eat or sleep, your breathing is getting faster, or your lips or fingertips are turning blue or grey. While you wait, sit up straight and take 1 puff of your blue reliever every 30 to 60 seconds, up to 10 puffs, through a spacer if you have one. If the ambulance hasn’t arrived after 10 minutes, repeat. Don’t complete an online consultation in an emergency.
Autumn asthma, the key facts: asthma attacks rise in the UK in September and through the autumn. Mould spores are high, children go back to school and spread colds and other viruses (the most common trigger for attacks), and cold, damp air irritates the airways. Many people also use their preventer less over the summer. Taking your preventer every day, a review before September, a flu jab if you’re offered one, and carrying your reliever are the best ways to stay ahead.
Order Your Asthma Inhaler Online
Access Doctor is a GPhC-registered pharmacy (#9011198). If you’re an adult with diagnosed asthma or COPD, a pharmacist independent prescriber reviews your online consultation and supplies your usual inhaler if it’s safe, and we let your GP know. Approved before 3pm, Monday to Friday? Dispatched the same day, by Royal Mail Tracked 48, Tracked 24 or Special Delivery guaranteed by 1pm next working day: you choose. Delivery is free on orders over £40.
Start Asthma Consultation →Who our online service is for. Access Doctor supplies asthma and COPD inhalers to adults aged 18 and over who already have a diagnosis, for the same inhaler, strength and dose they’re prescribed now, and we share the consultation with your GP. We can’t diagnose asthma or start or change treatment online. Children’s inhalers are managed by their GP or asthma nurse.
Why Is Autumn Bad for Asthma?
For many people with asthma, autumn, particularly September, is one of the hardest times of year. Asthma attacks and unplanned GP and hospital visits rise after children go back to school. Several things come together at once:
- Mould spores, such as Alternaria and Cladosporium, which are high from late summer into autumn
- Back-to-school viruses: colds (rhinovirus) are the most common trigger for asthma attacks
- Cold, damp air, which irritates sensitive airways
- Quick temperature changes, such as stepping from a warm room into cold air
- Preventers used less over the summer, leaving the airways more inflamed
For other triggers through the year, see our guide to asthma triggers.
Fungal Spores: The Overlooked Autumn Trigger
Most people know pollen is a spring and summer trigger, but in autumn mould spores take over. Moulds release tiny spores into the air, and in people who are allergic to them, breathing them in can trigger asthma. UK research has linked higher outdoor spore counts with more hospital admissions for asthma. The main moulds are:
Alternaria
Lives in soil and rotting leaves and plants. Levels are highest in late summer and early autumn. Sensitivity to it has been linked with severe asthma attacks.
Cladosporium
The most common outdoor mould in the UK. High from summer into autumn, especially on warm, windy days.
Aspergillus
Found indoors and outdoors. In some people with severe asthma it causes an allergic lung condition called ABPA, which needs specialist care.
Penicillium
A common household mould on damp walls, food and building materials. Can worsen asthma all year, often more in autumn and winter.
Spore levels are highest on warm, humid days after rain, especially near vegetation and fallen leaves. If you get bad asthma in late summer and autumn without an obvious cause, ask your GP whether allergy tests for moulds would help.
Cold and Dry Air
As the temperature drops, cold air takes heat and moisture from the airway lining, which can make the airways tighten in people with asthma. Damp autumn weather also encourages mould indoors and outdoors.
- breathe through your nose outdoors, which warms and moistens the air
- wear a loose scarf or snood over your nose and mouth in cold weather
- warm up gradually before outdoor exercise
- if your GP or asthma nurse has advised it, take 2 puffs of a blue reliever 10 to 15 minutes before outdoor exercise, or use your combination inhaler if you’re on AIR or MART (see our guide to exercise-induced asthma)
Back-to-School Viruses
The return to school in September is one of the biggest causes of the autumn rise. Schools spread viruses easily, especially rhinovirus, the common cold, which is the most common trigger for asthma attacks in children and adults. Viruses inflame and damage the airway lining and can leave the airways more sensitive for several weeks after the cold has gone.
The flu vaccine is free on the NHS for many people with asthma, including those who need a steroid preventer inhaler or tablets, and anyone who has been admitted to hospital with asthma. It doesn’t prevent colds, but it lowers your risk of flu, which can cause severe attacks. It’s usually offered from September or October; check with your GP or pharmacist. Have the COVID-19 and RSV vaccines too if you’re eligible.
The September Asthma Spike
Asthma attacks and unplanned medical visits rise sharply in the weeks after the return to school in September, a pattern sometimes called “September asthma” or the “September epidemic”.
- it’s most marked in school-age children, but adults are affected too, often after catching colds from children
- colds and other viruses spreading at school are thought to be the main driver
- UK data show prescriptions for preventer (steroid) inhalers drop in August compared with July and September, suggesting many children stop or run out of their preventer over the summer
Keeping up your preventer over the summer, and making sure you have enough before school starts, are simple ways to reduce the risk.
Weather Changes and Thunderstorm Asthma
Autumn weather in the UK changes quickly: warm days and cold nights, high humidity, rain and storms. Each can affect sensitive airways:
- Thunderstorm asthma: storms can break pollen grains and spores into tiny particles that reach deep into the lungs and cause sudden attacks in many people at once. It’s most often linked to grass pollen in early summer, but any storm on a high-pollen or high-spore day can be a risk; keep your reliever with you
- High humidity encourages mould growth indoors and outdoors
- Sudden temperature drops can trigger symptoms, especially when going from a warm home into cold air
Autumn Asthma Management Tips
Get ready before September to cut your risk of an attack:
Book an asthma review
See your GP or asthma nurse before September. Check your dose and inhaler technique, and update your written asthma action plan.
Take your preventer every day
Don’t let it lapse over the summer. Well-controlled airways cope better with autumn triggers.
Get your flu jab
Free on the NHS for many people with asthma, including those who need a steroid preventer. Usually offered from September or October.
Check the forecasts
Use the Met Office pollen forecast and local air quality. On bad days, cut time outdoors, keep windows closed and carry your reliever.
Avoid leaf piles and compost
Rotting leaves and compost release lots of mould spores. Wear a mask for gardening and try not to disturb leaf litter.
Reduce mould at home
Use extractor fans, air rooms, dry washing outdoors where you can, and deal with damp and visible mould promptly.
Your Asthma Action Plan for Autumn
Everyone with asthma should have a written asthma action plan from their GP or asthma nurse that says what to do as symptoms get worse. Follow your own plan; in general:
1
Every day (green)
Take your preventer or combination inhaler as prescribed, even when you feel well. Carry your reliever at all times, and check pollen and air-quality forecasts.
2
Getting worse (amber)
If you’re waking at night with asthma, needing your reliever more than usual or more than twice a week, or symptoms are stopping you doing things, follow your plan and contact your GP the same day or call NHS 111. Don’t wait for a severe attack. Your GP may change your treatment or prescribe a short course of steroid tablets.
3
Asthma attack (red)
Sit up straight. With a blue reliever such as Ventolin, take 1 puff every 30 to 60 seconds, up to 10 puffs, through a spacer if you have one; with an AIR or MART inhaler, take 1 puff every 1 to 3 minutes, up to 6 puffs. Call 999 if you feel worse at any point, you’re not better after the maximum puffs, or you don’t have your inhaler. If the ambulance hasn’t arrived after 10 minutes, repeat the puffs. See your GP within 2 days.
Our asthma attack guide has the full steps and warning signs.
Safety, your GP and free NHS options
Ventolin and other asthma inhalers are prescription-only medicines in the UK. Before anything is supplied, a GPhC-registered pharmacist independent prescriber reviews your consultation, including the other medicines you take; some, such as beta-blockers, can make asthma worse.
- Relievers on their own: since 2024, UK guidance (NICE, BTS and SIGN) says no one with asthma should be treated with a reliever alone, and in April 2025 the MHRA told prescribers not to prescribe one without an inhaled steroid to people of any age with asthma. If you don’t use a preventer, we can supply a reliever once and will ask you to see your GP or asthma nurse.
- How many: up to 2 reliever inhalers per order. If you’ve needed 3 or more in the last 12 months, we’ll ask you to have an asthma review first; needing that many is linked to a higher risk of severe attacks.
- Read the leaflet in the pack, and ask a pharmacist or asthma nurse to check your technique.
- Report side effects to a pharmacist or doctor. You can also report them to the MHRA through the Yellow Card scheme.
We share your consultation with your GP because asthma needs ongoing care. Access Doctor is a private service, and there are free NHS options:
- Your GP practice: asthma reviews (at least once a year) and repeat prescriptions; many practices let you order repeats through the NHS App.
- Prescription charges: NHS prescriptions are free in Scotland, Wales and Northern Ireland. In England a charge applies unless you’re exempt, and a prepayment certificate can save money if you need several items.
- Urgent advice: NHS 111 (NHS 24 on 111 in Scotland), or 999 in an emergency.
Need Your Usual Inhaler Before Autumn?
Access Doctor is a GPhC-registered pharmacy (#9011198). If you’re an adult with diagnosed asthma or COPD, a pharmacist independent prescriber reviews your online consultation and supplies your usual inhaler if it’s safe, and we let your GP know. Approved before 3pm, Monday to Friday? Dispatched the same day, by Royal Mail Tracked 48, Tracked 24 or Special Delivery guaranteed by 1pm next working day: you choose. Delivery is free on orders over £40.
Start Asthma Consultation →Frequently Asked Questions
Why does asthma get worse in autumn?
Several things come together in autumn: mould spore levels are high, children go back to school and spread colds and other viruses, cold and damp air irritates the airways, and the weather changes quickly. Some people also take their preventer less regularly over the summer. Together, these explain why asthma attacks and hospital visits rise in September and through the autumn in the UK.
What is September asthma?
September asthma is the well-known rise in asthma attacks and unplanned visits to GPs and hospitals in the weeks after children go back to school in September. It’s most marked in school-age children, but adults are affected too. The main drivers are thought to be colds and other viruses spreading at school, together with preventer inhalers being used less over the summer holidays. UK data show inhaled steroid prescriptions drop in August.
How can I prevent autumn asthma attacks?
Take your preventer every day, including over the summer. Book an asthma review before September to check your dose, technique and action plan. Have the flu vaccine if you’re offered it. Carry your reliever at all times. Reduce exposure to mould by avoiding leaf piles and compost and dealing with damp at home. Wear a scarf over your nose and mouth in cold air, and warm up before outdoor exercise.
Are fungal spores worse than pollen for asthma?
For people who are allergic to them, mould spores can be at least as troublesome as pollen. Sensitivity to some moulds, particularly Alternaria, has been linked with severe asthma attacks. Outdoor spore levels in the UK are high from late summer into autumn, especially on warm, humid days after rain. If your asthma is worse in late summer and autumn but not spring, ask your GP whether allergy tests for moulds would help.
Is the flu jab free for people with asthma?
For many people with asthma, yes. The NHS offers a free flu vaccine to people with asthma who need a steroid preventer inhaler or tablets, or who have been admitted to hospital with asthma, as well as to other eligible groups such as everyone aged 65 and over. Ask your GP or pharmacist, or check the NHS flu vaccine page. The vaccine doesn’t protect against colds, but it lowers your risk of flu, which can cause severe asthma attacks.
What should I do if I have an asthma attack in autumn?
Follow the same steps as at any time of year. Sit up straight and try to keep calm. With a blue reliever, take 1 puff every 30 to 60 seconds, up to 10 puffs, through a spacer if you have one; with an AIR or MART inhaler, take 1 puff every 1 to 3 minutes, up to 6 puffs. Call 999 if you feel worse at any point, you’re not better after the maximum puffs, or you don’t have your inhaler. See your GP within 2 days afterwards.
For symptoms, triggers and how asthma is diagnosed, see our asthma guide.
References
- Horspool MJ, Julious SA, Boote J, et al. Preventing and lessening exacerbations of asthma in school-age children associated with a new term (PLEASANT): study protocol for a cluster randomised control trial. Trials 2013;14:297. pmc.ncbi.nlm.nih.gov
- Johnston SL, Pattemore PK, Sanderson G, et al. Community study of role of viral infections in exacerbations of asthma in 9–11 year old children. BMJ 1995;310:1225–1229.
- Newson RB, Strachan DP, Corden J, Millington W. Fungal and other spore counts as predictors of admissions for asthma in the Trent region. Occup Environ Med 2000;57:786–792.
- NHS. Flu vaccine. nhs.uk
- NHS. Asthma attack. nhs.uk
- NICE, BTS and SIGN. Asthma: diagnosis, monitoring and chronic asthma management (NG245), November 2024. nice.org.uk
- MHRA Drug Safety Update. Short-acting beta-2 agonists (SABA): reminder of the risks from overuse in asthma and changes in the SABA prescribing guidelines, April 2025. gov.uk
Medical disclaimer: This article is for informational purposes only and does not constitute medical advice. Always consult a qualified healthcare professional for diagnosis and treatment. In a medical emergency, call 999.