Your sinuses are small air-filled cavities behind your cheekbones and forehead. They make mucus which normally drains away through small channels into the nose, but if they become inflamed - usually due to a viral infection - mucus can build up and sinusitis can develop.
Your sinuses can become inflamed for a number of reasons, but this most likely to happen when you have a cold or flu or other infection as the inflammation stops mucus draining away as normal.
Hay fever, dental infections, growths such as nasal polyps and other allergies can also affect your sinuses. Gastro-oesophageal reflux disease (GORD), where stomach acid leaks up into the oesophagus, may also obstruct your sinuses.
Sinusitis can make you feel groggy and unwell. Headache and pain that spreads over your cheek bones, across your brow, or into your teeth and ears are common symptoms. You may also have a blocked nose, a cough, bad breath, a sore throat and thick, green or yellow mucous nasal discharge or mucus dripping down into your throat. Your sense of taste and smell may also be affected.
Acute infection can last up to 12 weeks, but usually resolves within two-and-a-half weeks and chronic infections last more than 12 weeks.
Describing your symptoms to your GP should be enough to allow them to diagnose sinusitis. Your GP may check the lining of your nose, as this can be swollen if you have acute sinusitis and ask you about any discharge. They may also check the other sinus areas, to see whether they are sensitive. Some people find the pain is worse when they bend forward.
Who gets sinusitis?
You're more likely to develop sinusitis if you have had a cold or flu virus that has travelled to your sinuses. You're also at greater risk if you have hayfever, or other allergies that have already affected your sinuses.
Other possible causes include fungal infections, or dental infections.
Having a deviated nasal septum, where the thin barrier between your nasal passages is further over to one side, and not in the middle, nasal polyps, growths on your sinuses or nasal passages, or tumours, and more serious conditions, such as cystic fibrosis, or HIV/AIDS or other immune system problems can also increase your risk of developing sinusitis.
In most cases, simple painkillers, such as paracetamol or ibuprofen will be enough to help ease the pain. Your nose may be bunged up, in which case your GP may also suggest that you use a nasal decongestant for a week, and try flushing your nostrils out with a salt water (saline) solution.
Putting a warm (not hot) face pack, or flannel on your face may help relieve some of the pain. If your sinusitis is particularly uncomfortable or goes on for a long time, it may be worth asking your GP about corticosteroid sprays that are applied directly into your nose.
Sinusitis is caused by a virus in most cases, but antibiotics such as amoxicillin may be prescribed if a bacterial infection is suspected.
If your acute sinusitis develops into a severe infection, or you develop complications such as double vision, swelling, or symptoms of meningitis, see your doctor as you may need to be admitted to hospital for treatment. However, these severe complications only happen in around one in 10,000 cases of acute sinusitis.
In chronic sinusitis, your doctor will advise you to continue taking the measures above to deal with symptoms and you may need to take nasal steroids for up to three months.
Getting treatment for related illnesses such as dental infections and allergies is also advised. If you have frequent or recurrent attacks you may need to see an ear, nose and throat (ENT) specialist.