Cough with phlegm and runny nose: what to know

A runny nose can send mucus down the back of the throat, creating a cough and the feeling of phlegm. Common cold symptoms often include congestion, throat irritation, and tiredness. Allergic rhinitis may cause a clear runny nose, sneezing, itchy eyes, or symptoms linked to pollen, dust mites, or pets. Influenza and COVID-19 can also cause cough and other respiratory symptoms, sometimes with fever, aches, or marked fatigue. Sinusitis may be considered when facial pressure, blocked nasal passages, or symptoms that worsen after initial improvement are present. These patterns overlap, so symptoms alone may not identify one condition.

Rest, drink enough fluid to keep urine reasonably pale, and use saline spray or rinsing to clear nasal mucus. Wash hands, ventilate shared spaces, and consider staying away from vulnerable people while you are acutely unwell. Avoid smoke and strong fragrances. A pharmacist can help select symptom relief that fits your age, pregnancy status, medical conditions, and current medicines. Do not combine products with the same active ingredient.

Get urgent help for severe breathing difficulty, blue lips, confusion, fainting, or chest pain. Arrange medical advice for dehydration, persistent or returning fever, worsening facial pain, wheezing, coughing blood, or symptoms that are not improving. If you may have COVID-19 or influenza, follow current local advice about testing and contact with others, especially around people at higher risk of severe illness.

Is the phlegm likely coming from nasal drainage or the lower airways? Could allergies, sinusitis, or a viral infection explain my symptoms? Which medicines can I safely combine? When can I return to work or normal activities?