What should you know about constant shortness of breath?

Breathlessness may come from Asthma, COPD, bronchiectasis, or a recent respiratory infection such as Acute Bronchitis. Anaemia can reduce the blood's oxygen-carrying capacity and make exertion feel harder. Angina or an irregular rhythm such as Atrial Fibrillation can affect how the heart responds to activity. Anaphylaxis can narrow the airways quickly. The pattern matters: note whether symptoms occur at rest, with exertion, when lying down, or with wheeze, cough, fever, chest discomfort, palpitations, or swelling.

If breathlessness is new, persistent, or limiting normal activity, arrange medical assessment promptly. Sit upright, loosen tight clothing, avoid smoke, and use a prescribed reliever inhaler exactly as your action plan says. Do not borrow someone else's inhaler or assume anxiety is the explanation before physical causes are considered. Write down onset, triggers, activity level, cough, wheeze, chest symptoms, palpitations, fever, leg swelling, and medicines. A clinician may check breathing, heart rhythm, oxygen level, and blood tests or imaging when appropriate.

Call emergency services for severe or rapidly worsening breathlessness, inability to speak comfortably, blue or grey lips, fainting, confusion, severe chest pain, or sudden swelling of the face, lips, or tongue. Urgent assessment is also needed for breathlessness at rest, coughing blood, new one-sided leg swelling, or a new irregular heartbeat with weakness or chest discomfort. Keep prescribed emergency medicines available and do not drive yourself if symptoms are severe.

Could my symptoms be related to asthma, infection, anaemia, heart rhythm, or another cause? Which examinations or tests are appropriate? What action plan should I follow if breathlessness returns, and which changes require emergency help?