A cough is a normal bodily response that’s designed to clear mucus and other irritants from the lungs.
In most cases, it’s nothing to worry about and gets better on its own. Sometimes, however, a cough can be a sign of a condition that needs medical attention.
But how can you tell when it’s time to worry about a cough? The length of time you’ve had the cough often provides a clue.
Types of coughs
A cough can be defined by how long it lasts. The different types are:
- acute coughs - last for less than 3 weeks
- subacute coughs - last for 3 to 8 weeks
- chronic coughs - last for more than 8 weeks
An acute cough is usually caused by a viral illness like the. It typically clears on its own after a couple of weeks. However, subacute and chronic coughs should always be assessed by a doctor.
When to see a doctor about an acute cough
An acute cough is usually caused by a viral infection of the nose, sinuses and/or throat (known as the upper respiratory tract). These are infections like a cold or the flu. But a cough can also be caused by infections or inflammation of the lungs and airways, such asor .
An acute cough can also be triggered by an allergy or a flare-up of a long-term condition like.
This type of cough can usually be treated at home with plenty of rest and fluids. However, see a doctor if:
- your cough is severe or getting worse, or you’re constantly coughing or have a hacking cough
- you feel very ill
- you have chest pain
- you are losing weight without trying to
- you have swollen glands (feel the side of your neck to check for swelling)
- you’re finding it difficult to breathe
- you have a weakened immune system (e.g. caused by chemotherapy or conditions like diabetes)
You should seek immediate medical help if you’re coughing up blood.
When to see a doctor about a subacute or chronic cough
If you’ve had a cough for more than 3 weeks, see a doctor. Your cough may be caused by conditions, including:
- postnasal drip
- certain medications
In rare cases, a persistent cough can be a sign of a more serious underlying condition.
When to see a doctor urgently
If you’re coughing up blood you should see a doctor urgently.
A cough is not usually anything to worry about, and should clear up on its own within 3 to 4 weeks. However, if you experience any of the concerning symptoms mentioned in this article or you’re worried about your cough, see a doctor.