Severe persistent asthma: when asthma is hard to control and what specialists can offer

Most people with asthma have symptoms that settle with a preventer inhaler taken as prescribed. The NHS notes that for most people inhalers work well and asthma has only a small impact on daily life, but that some people have more severe symptoms that are harder to control and need other treatment. Asthma + Lung UK describes severe asthma as asthma that is hard to control with the usual asthma medicines. It is the most serious type of asthma and needs specialist treatments.

Terms vary. The phrase 'severe persistent asthma' is still widely searched for, but the UK patient information read for this page, from Asthma + Lung UK and the NHS, uses the terms 'severe asthma' and, separately, 'difficult' or 'hard to control' asthma. The content below follows those sources.

Asthma + Lung UK explains that a GP may say you have 'difficult asthma' if, in the last 12 months, you needed two or more courses of steroid tablets, went to hospital or A&E at least once for your asthma, were prescribed six blue relievers, had lots of symptoms despite high-dose treatment, or have been on maintenance steroid tablets. There can be many reasons why asthma is hard to control, such as allergies, stress or other medical conditions, and most people with difficult asthma do not have severe asthma.

The charity says not taking your inhaler regularly and incorrect inhaler technique are common causes of uncontrolled inflammation. This is why the first step is a careful review rather than an immediate move to specialist drugs. If your asthma improves with support and a good medicine routine, you do not have severe asthma.

The NHS lists the main symptoms of asthma as wheezing, coughing, shortness of breath and a tight chest, which usually come and go and may be worse at night and early in the morning. Asthma + Lung UK says that with severe asthma you may have lots of these symptoms most days, have frequent attacks which can happen without warning, and find symptoms hard to control even on higher doses of medicine. Having these symptoms does not always mean you have severe asthma.

See your GP or asthma nurse if you get lots of symptoms a lot of the time, need your reliever a lot, wake at night because of asthma, find daily activities difficult or have frequent attacks. The NHS says to call 999 during an asthma attack if you feel worse at any time, do not feel better after the maximum dose of your reliever, or do not have an inhaler, and not to drive yourself to A&E. After an attack you should see a GP within 2 days, even if you feel better.

Asthma + Lung UK says most people with difficult or severe asthma have a more severe type of airway inflammation called Type 2 inflammation, linked to allergies or higher levels of a blood cell called an eosinophil. Specialists may describe the type, or phenotype, of severe asthma.

According to Asthma + Lung UK, if your symptoms are hard to control you should see your GP, who can review what is causing them: missed doses, inhaler technique, triggers such as smoking, vaping or workplace dust, mental wellbeing, allergies and conditions such as obstructive sleep apnoea, obesity, acid reflux, anxiety and depression, which can all make asthma harder to control. Your GP may arrange tests such as FeNO (fractional exhaled nitric oxide), spirometry or blood tests.

If symptoms are still not well controlled after a review, the GP should refer you to a specialist asthma team. The charity notes that doctors may say your asthma is difficult to control for some time before confirming severe asthma, to make sure the right things have been tried.

The NHS says that if inhalers are not enough, a stronger inhaler or tablets such as montelukast may be added, and that severe asthma not controlled by inhalers and tablets may be treated with injected biological therapies. Asthma + Lung UK describes the main specialist options below.

Asthma + Lung UK advises that anyone on long-term steroid tablets who has not seen a specialist should ask the GP for a referral, so that other, safer treatments can be considered, and that coming off steroids needs to be done slowly under specialist supervision to avoid adrenal insufficiency. Practical tips include taking medicines at the same time each day, using reminders and repeat prescriptions, keeping the asthma action plan with your medicines, and tracking symptoms with a diary, peak flow or an app so that worsening is spotted early.

The NHS adds that you should have an asthma review at least once a year, avoid triggers, keep to a healthy weight, have vaccinations such as the flu vaccine, and avoid smoking. Some medicines, including aspirin, ibuprofen and beta blockers, can trigger asthma symptoms in some people, so check with a pharmacist or doctor before starting medicines for other conditions.

Severe asthma services are usually NHS specialist clinics reached by GP referral, and biologics are typically supplied through these services. Private respiratory consultations exist, but biologic therapy is usually delivered through NHS specialist centres, so a private opinion should be shared with your NHS asthma team.