Breathlessness, known medically as dyspnea, is when people describe a feeling of being out of breath, short of breath or they find it uncomfortable to breathe. It is an unpleasant feeling which can happen to anyone. If it occurs outside of a situation you would normally expect, for example when exercising, or if it is accompanied by other symptoms such as chest pain, it is important to speak to your doctor right away to rule out a concerning underlying cause. Because there are so many possible reasons for feeling breathless, always speak to your doctor about it if it happens to you.

A cough is the body’s natural way of responding to irritation in your respiratory tract. When specialized sensors in your airways detect an irritant such as smoke, dust or pollution, it triggers a cough reflex that causes the muscles in your airways to contract and pushes a burst of air out through your airways in an attempt to remove the cause of the irritation – this is a cough. A dry cough is when you cough without bringing up any mucus or phlegm and can be irritating for your throat. It is a very common type of cough that can be caused by an infection, asthma, environmental irritant or irritation caused by acid reflux. It may also be a side effect of certain medications such as ACE inhibitors, used to treat high blood pressure. A constant dry cough is the result of your cough reflex becoming more sensitive than usual.

Phlegm, also known as mucus, is produced by your lungs to line the airways and protect them from foreign substances. It provides moisture which helps to trap irritants and remove them from the body. In certain situations, your body might increase the production of mucus, for example, when you have an allergy or an infection, which might cause unpleasant symptoms. When you cough up phlegm from the lungs or back of the throat, it's often referred to as sputum. Looking at your phlegm or sputum can give you a lot of information about what could be causing your symptoms.

A blocked nose is the feeling that the nasal passages are congested or stuffy. Depending on the individual, a blocked nose can affect each person quite differently. A blocked nose can occur over a short period (acute) or a long period (chronic) of time, which is usually regarded as more than three months. A blocked nose can occur with other symptoms which may give an indication of the cause; for example, nasal discharge (rhinorrhea), loss of sense of smell or taste (anosmia), sneezing and irritation, pain in the face, or nasal bleeding.

A cough is the body's natural way of responding to irritation in your respiratory tract, causing muscles in the airways to contract and push out any irritant or infection in a burst of air. Your airways are covered in cells that produce mucus which aids in the removal of dust, bacteria, viruses, and other debris. When you get a chest infection, your body produces more mucus than normal as it tries to remove the virus or bacteria. The excess mucus, known as phlegm or sputum, causes you to cough more frequently and forcefully – phlegm is then brought up and spat out or swallowed, destroying the pathogen and helping you recover. We call this a productive cough. Most chest infections and productive coughs are caused by viruses rather than bacteria. As antibiotics only work on bacterial infections, this means that they won't have any effect on most chest infections.

Blood in the sputum is also known as hemoptysis. Sputum is usually the mucus substance you cough up from the airways and lungs. Phlegm is the specific term for the mixture of saliva and mucus from your nose, mouth, and throat. There can be different causes for hemoptysis; some are serious, and some are less so, but you should see your doctor in most circumstances, so they can work out the underlying cause. You may notice a few streaks of blood in the sputum, which commonly come with a chest infection, or clots, or even a pink watery appearance. Still, these indicate an area of tissue damage and warrant a discussion with your doctor.