Sinusitis: causes, symptoms, and when to seek help
Sinusitis occurs when the sinuses—air-filled spaces behind your cheekbones and forehead—become inflamed. This inflammation can lead to a blocked nose, facial pain, and other uncomfortable symptoms. While sinusitis is usually not serious, it can affect your quality of life.

Cause of sinusitis
In most cases, sinusitis is caused by a viral infection, such as a cold or the flu, and resolves within a few weeks. However, certain conditions or lifestyle factors can make you more prone to developing sinusitis.
When the sinuses are blocked, mucus builds up, creating an environment where infections can develop. This can result in sinus pain and pressure in the face.
Sinusitis happens when the lining of the sinuses becomes inflamed or infected, most commonly due to:
Viral infections – Such as a cold or flu
Allergies – Triggers like pollen, dust mites, or pet dander can lead to inflammation
Environmental irritants – Exposure to smoke, pollutants, or strong odours can irritate the sinuses
Nasal blockages – Conditions like nasal polyps or a deviated septum may prevent proper drainage of the sinuses
Lifestyle factors – Smoking, pregnancy, and activities like swimming or diving can increase your risk

What are the symptoms of sinusitis?
- Sinusitis often develops following a cold or flu. The most common symptoms include:
- Green and yellow mucus from the nose – you may notice this when you blow your nose
- A reduced sense of smell
- Toothache
- Headache
- Fever
- Bad breath
You might notice sinusitis symptoms during air travel, as changes in cabin pressure can cause sharp pain in the face if your sinuses are inflamed. While it’s safe to fly with sinusitis, you may want to use a decongestant spray to manage symptoms.
In rare cases, severe sinus infections can spread and cause more serious issues, such as swelling around the eyelids or a stiff neck. If you experience these symptoms, seek urgent medical attention.

How can I treat sinusitis at home?
You can use over-the-counter decongestant sprays or drops to relieve a blocked nose. Be sure to follow the instructions and avoid overusing these products, as they can worsen symptoms if used for too long.
Most cases of sinusitis resolve on their own within a few weeks. You can manage your symptoms at home with simple remedies, such as:
Staying hydrated – Drink plenty of water to thin mucus and promote drainage.
When should I speak to a GP or Advanced Clinical Practitioner (ACP)?
You should seek medical advice if your sinusitis symptoms:
- Are very severe or getting worse
- Don’t improve after 10 days
- Keep coming back
- Are accompanied by persistent pain, swelling, or a high fever
A doctor or ACP can prescribe treatments such as steroid nasal sprays, antihistamines, or antibiotics if a bacterial infection is suspected. In rare cases, chronic sinusitis may require specialist treatment, such as surgery to widen the sinuses or remove blockages.
How can I avoid getting sinusitis?
Preventing sinusitis can be challenging since it often follows a cold or flu. However, you can reduce your risk by:
- Practising good hygiene to avoid viral infections
- Quitting smoking
- Keeping allergies under control
If you do catch a cold, take care of yourself by resting, staying hydrated, and treating your symptoms with over-the-counter products.
What else could be causing my symptoms?
The symptoms of sinusitis may indicate another condition, such as nasal polyps. Nasal polyps are soft, painless growths inside the nose that can block the sinuses and cause:
- A blocked or runny nose
- A reduced sense of smell
- Nosebleeds
Nasal polyps need to be diagnosed by a doctor or ACP and can be treated with steroid nasal sprays, tablets, or surgery if necessary.
