Acute bronchitis runs under 3 weeks by definition - and the cough is usually the last symptom standing.
The CDC is direct: it is almost always viral, it gets better on its own, and antibiotics will not help. The airway stays irritable after the infection clears, which is why the cough nags. Past 3 weeks, repeated episodes, breathing trouble, high fever, or blood in the cough: get seen - pneumonia and asthma wear bronchitis's clothes.
What to do
Common questions
How long does bronchitis last?
Acute bronchitis - the chest cold - runs under 3 weeks by definition, and the cough is nearly always the last symptom standing after the sore throat, congestion, and aches have cleared. The CDC is direct about the cause and the treatment: a virus usually causes it, it usually gets better on its own, and antibiotics will not help - taking them anyway buys side effects and resistance risk for zero benefit. The frustrating part is that the airway stays irritable after the infection clears, which is why the cough can nag through the full three weeks even as you feel otherwise fine. The lines that change the diagnosis: a cough lasting more than 3 weeks, repeated bronchitis episodes, shortness of breath or trouble breathing, high fever, or coughing blood - all reasons to be seen promptly, since pneumonia, asthma, and other conditions wear bronchitis's clothes. Smoking stretches every respiratory infection longer; quitting shortens them all. Pymander, a free AI doctor available 24/7 by text, can help you judge a lingering cough.