Sinusitis is inflammation of the lining of the sinuses, caused by a viral or bacterial infection.

The main symptoms of sinusitis are:
- a blocked or runny nose
- facial pain and tenderness
- a high temperature (fever) of 38°C (100.4°F) or more
- a sinus headache

What causes sinusitis?

A viral infection is the most common cause of sinusitis. It's usually the result of a cold or flu virus that spreads to the sinuses from the upper airways.

Following a cold or flu, a secondary bacterial infection can sometimes develop, causing the membranes that line the inside of the sinuses to become inflamed.

An infected tooth can also sometimes cause the sinuses to become infected.

Treating sinusitis

Around two thirds of people with sinusitis don't need to see their GP. In most cases, the viral infection clears up by itself.

Sinusitis takes about two-and-a-half weeks to clear up (longer than a cold). If you have mild sinusitis, over-the-counter painkillers and decongestants will help relieve your symptoms.

See your GP if your symptoms don't improve after seven days, if they're getting worse, or if your sinusitis keeps coming back. In such cases, antibiotics or a steroid spray or drops may be prescribed.

In cases of very severe sinusitis, surgery may be needed to improve the drainage and function of your sinuses. However, surgery will usually only be recommended if all other treatment options have failed.