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Overview: Asthma

Last Update: July 20, 2022; Next update: 2025.


In asthma, people's airways become so narrow (temporarily or permanently) that it's difficult for them to breathe. Asthma typically comes in episodes or "attacks” of wheezing, coughing and shortness of breath. Without proper treatment, the lungs may gradually take in less oxygen, affecting your general physical fitness.

But asthma doesn't always get worse. Nowadays, asthma can be treated quite effectively using medicine and other interventions such as regular exercise. Most people with asthma can manage their illness and live a mostly symptom-free life. It's important to know what you can do on your own, and to find out what kind of treatment is best suited to you.

At a glance

  • In asthma, people's airways become narrow.
  • This is due to the immune system overreacting to certain substances.
  • An asthma attack can cause shortness of breath, chest tightness and coughing.
  • Asthma can be treated effectively with medication.
  • Certain breathing techniques and exercise can be used to support the treatment.
  • Managing asthma well can prevent lasting physical effects.


Common asthma symptoms in children include coughing and whistling or wheezing sounds when breathing. Other typical signs of asthma are usually not yet present. In teenagers and adults, asthma is characterized by the following symptoms:

  • Shortness of breath (often in sudden attacks)
  • Breathlessness when exercising
  • Sounds when breathing (out): e.g. wheezing, whistling, rattling
  • Chest tightness
  • Coughing and/or the urge to cough

These symptoms mostly happen in episodes or attacks, often at night too. This is one of the reasons why some people who have this chronic illness often feel so tired and groggy during the day. During an asthma attack, initial minor breathing difficulties can get worse and develop into more serious shortness of breath.

Causes and risk factors

Asthma is more common in some families than in others, which suggests that genes might play a role. Further risk factors include a low birth weight, and having other allergy-related conditions such as hay fever or eczema, either yourself or in your family. Asthma is more common in boys than in girls. Children are more likely to get asthma if they’re exposed to cigarette smoke. Parents who smoke can reduce this risk by kicking the habit.

Asthma symptoms occur when two things come together: People with asthma have an immune system that permanently tends to overreact. This tendency goes mostly unnoticed until the mucous membranes that line the insides of the bronchi come into contact with specific triggers.

Depending on the type of trigger, doctors classify asthma as being either allergic or non-allergic.

  • Allergic asthma is also called “extrinsic asthma” because the trigger comes from outside the body and is breathed in with the air. Different people may have reactions to very different types of triggers, including cigarette smoke (active and passive smoking), plant pollen, animals, dust mite excrement, and some kinds of food as well as cold air, perfume, exhaust fumes and certain chemicals.
  • Non-allergic asthma (also called “intrinsic asthma”) is caused by triggers that come from inside the body. These triggers include bacterial and viral inflammations of the airways in particular. Sometimes taking certain kinds of painkillers causes asthma. These painkillers include acetylsalicylic acid (ASA, the drug in medicines like Aspirin) and other non-steroidal anti-inflammatory drugs (NSAIDs). In some people, physical or emotional stress that makes them breathe faster can also trigger asthma symptoms.

Factors inside and outside the body often play a role, so it isn't always clear whether it is allergic asthma or non-allergic asthma. The effects on the lungs and breathing are nearly the same though:

  • Immune system cells in the membranes lining the bronchi are activated,
  • the muscles surrounding the airways tense up,
  • the mucous membranes lining the airways become inflamed and swollen, and
  • very thick and sticky mucus is often produced.

The muscles tensing up, the swelling of the mucous membranes and the extra mucus production all cause the airways to become narrower and narrower, resulting in an asthma attack.

Illustration: Structure of the airways in the lungs: healthy bronchi and bronchi narrowed by asthma – as described in the article

Structure of the airways in the lungs: healthy bronchi and bronchi narrowed by asthma

Prevalence and outlook

About 4% of children and 6% of adults in Germany have asthma. Asthma is the most common chronic disease in children.

The course of asthma can vary greatly, and it doesn’t always get worse over time. Some people who have asthma as children or teenagers have hardly any symptoms, or even none at all, as adults. In other people the symptoms stay the same or get worse. A lot depends on how easy it is to avoid the asthma triggers, how effective the asthma treatment is, and how you cope with the disease yourself. Medication and other interventions, such as special breathing techniques, can help make it possible to live an almost normal life.

Asthma can develop at any age. But it often first occurs in childhood or teenage years. People who have asthma frequently also have allergies such as hay fever, allergic conjunctivitis, or eczema. So their symptoms might change depending on the season or other factors, or they may disappear completely for a while, or even for good. Sometimes other allergy symptoms then become more dominant again, and it may be a while until the asthma symptoms return.


Doctors are only able to determine whether the symptoms are caused by asthma or another illness if they consider their patient’s symptoms and various test results together. The diagnosis of asthma usually involves:

  • An in-depth talk with the doctor (anamnesis): This will cover things like the type of symptoms, medical history and aspects of the person's lifestyle.
  • Physical examination: Your lungs, heart and circulation are checked, as well as your general health.

Lung performance can be measured using a lung function test (spirometry, peak flow measurement). In spirometry, both the amount of air you breathe out and how fast you blow it out are measured. The peak flow meter measures how fast you can blow air out of your lungs.

Other breathing or allergy tests may be needed to be absolutely sure of the diagnosis.


The main goal of asthma treatment depends on your own needs. It usually involves reducing the frequency and the severity of the symptoms as much as possible. The treatment should also help people with asthma to live as normal a life as possible. It is important to know that asthma treatment with medication has very few side effects. This is also the case for women with asthma who are pregnant. A doctor can help you decide which medications could be used.

Two main groups of medications are used to treat asthma:

  • fast-acting medication that is taken when needed (reliever or “rescue” medication), and
  • slow-acting medication that is taken regularly (controller or preventer medication).

If you have mild asthma, you may just need to use a reliever. Then you only take the medication when you have symptoms.

But more severe asthma can usually only be managed by using controller medication. These reduce the chronic inflammation in the airways, and this helps prevent asthma attacks. They are typically used on a daily basis. The choice of treatment always depends on how severe the symptoms are. The medication can only offer enough protection from asthma attacks if it is used consistently.

Trying to avoid contact with asthma triggers can help too. That's not always easy to do in daily life, though, and may sometimes be impossible. Finding out whether you are sensitive to animals, dust mites or cold air can be helpful. But avoiding those triggers doesn’t always prevent asthma symptoms from occurring. Most people who have asthma don’t need to worry too much about the triggers if they use their medication correctly.

Sports and exercise, as well as certain breathing techniques, can also help to keep the symptoms under control. Although these don’t usually work without using medication too, the two approaches complement each other well. It’s best to talk with your doctor about which treatments are most suited to reaching your goals.

It may also be a good idea to be vaccinated against the flu or pneumococci.

Everyday life

Like most chronic diseases, asthma doesn’t only affect one single organ – in this case, the lungs – but the whole person. For example, if you can't sleep at night because of asthma attacks, you'll be tired and unable to concentrate properly during the day. Your physical fitness can also be affected.

It often takes a while to learn to live with a chronic disease. Your family and friends may need some time to get used to it too. Getting enough information can help both children and adults to cope better with asthma and become more independent. Being well-informed often helps people deal with critical situations like an asthma attack. This may avoid emergencies and the need for hospital stays. Support groups can offer valuable support in coping with asthma.

Further information

Disease management also includes knowing where to find support, advice and the best possible treatment. Advice from doctors, good patient education or joining a support group can help you become an expert in handling asthma yourself. Patient education is offered by lung specialists and specialized rehabilitation facilities, for instance. The aim is to learn

  • what causes asthma and how it can be treated
  • how to recognize early signs of an asthma attack,
  • how to avoid triggers, and
  • what people with asthma and those around them can do in an emergency situation.

Asthma support groups are organized by people who have asthma or are close to someone who has asthma. They provide the opportunity to share experiences and support each other. This can help you to cope with asthma and understand the disease better.


  • Bundesärztekammer (BÄK), Kassenärztliche Bundesvereinigung (KBV), Arbeitsgemeinschaft der Wissenschaftlichen Medizinischen Fachgesellschaften (AWMF). Nationale Versorgungsleitlinie: Asthma. AWMF-Registernr.: nvl-002. 2020.
  • Dennis RJ, Solarte I, Rodrigo G. Asthma in adults. BMJ Clin Evid 2011: 1512. [PMC free article: PMC3275169] [PubMed: 21749735]
  • Global Initiative for Asthma (GINA). Global Strategy for Asthma Management and Prevention (Update). 2021.
  • IQWiG health information is written with the aim of helping people understand the advantages and disadvantages of the main treatment options and health care services.

    Because IQWiG is a German institute, some of the information provided here is specific to the German health care system. The suitability of any of the described options in an individual case can be determined by talking to a doctor. informedhealth.org can provide support for talks with doctors and other medical professionals, but cannot replace them. We do not offer individual consultations.

    Our information is based on the results of good-quality studies. It is written by a team of health care professionals, scientists and editors, and reviewed by external experts. You can find a detailed description of how our health information is produced and updated in our methods.

© IQWiG (Institute for Quality and Efficiency in Health Care)
Bookshelf ID: NBK279520


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