What are sinuses?
The sinuses are small, air filled spaces inside the cheekbones and forehead. They make some mucus which drains into the nose through small channels.
What is sinusitis?
Sinusitis means inflammation of a sinus. Most bouts of sinusitis are caused by an infection. The cheekbone (maxillary) sinuses are the most commonly affected.
Acute sinusitis means that the infection develops quickly (over a few days) and lasts a short time. Most last no more than a week or so but some last longer.
A mild bout of acute sinusitis is common as many people will have some degree of sinusitis with a cold. However, severe acute sinusitis is uncommon. Many people only ever have one or two bouts of acute sinusitis in their life. However, some people have recurring bouts of acute sinusitis.
Chronic sinusitis means that a sinusitis becomes persistent. Symptoms can last for months or longer. Chronic sinusitis is uncommon and is discussed further in a separate leaflet.
How do you get acute sinusitis?
- In most cases, acute sinusitis develops from a cold or flu-like illness. Colds and flu are caused by viruses which may spread to the sinuses. The infection may remain 'viral' before clearing. In some cases, bacteria 'add-on' to an infection that started with a virus. This can make the infection worse and last longer.
- In some cases, infection spreads to a maxillary sinus from an infected tooth.
- In a few cases, one or more factors are present that may cause the sinuses to be more prone to infection. These include:
- Allergic rhinitis (nose allergy). The allergy may cause swelling of the tissues on the inside lining of the nose and block the sinus drainage channels. See separate leaflet called 'Allergic Rhinitis'.
- Other causes of a blockage to the sinus drainage channels such as nasal polyps, objects pushed into the nose (especially in children such as peas or plastic beads), facial injury or surgery, and certain congenital abnormalities in children.
- Cystic fibrosis.
- A poor immune system, for example, people with HIV, people on chemotherapy, etc.
- Inflammatory disorders such as Wegener's granulomatosis or sarcoidosis.
- Pregnancy, which makes you more prone to rhinitis (nose inflammation).
- Primary ciliary dyskinesia / Kartagener's syndrome.
- Rare tumours of the nose.
Once the lining of the sinus is infected, the sinus cavity fills with extra mucus, and sometimes pus.
What are the symptoms of acute sinusitis?
Symptoms that commonly occur include:
- Pain and tenderness over the infected sinus. The pain is often throbbing, and worse when you bend your head forward. Chewing may be painful.
- Blocked nose. Your sense of smell may also go for a while.
- A runny nose. The discharge may be greeny/yellow due to infected mucus and pus. A runny nose may dry up if the sinus drainage channels become blocked with thick mucus. If this happens, pain and tenderness over the infected sinus may become worse.
- High temperature (fever) may develop, and you may feel generally unwell.
Other symptoms that may occur include: headache, bad breath, toothache, cough, a feeling of pressure or fullness in the ears, and tiredness. In children, symptoms may include irritability, snoring, mouth breathing, feeding difficulty, and 'nasal' speech.
What are the treatments for sinusitis?
- Often, no treatment is needed. Most cases are due to a virus infection. Like with colds, the immune system usually clears the virus, and symptoms usually go within a week or so. Even if the infection is caused by bacteria, the immune system will usually clear it away.
- Painkillers such as paracetamol or ibuprofen will usually ease any pain. Sometimes stronger painkillers such as codeine are needed for a short time.
- Antibiotics are sometimes useful. Your doctor is not likely to prescribe an antibiotic for a mild bout of acute sinusitis. This is because acute sinusitis usually clears on its own, and there is a risk of side-effects from antibiotics. Antibiotics do not kill viruses, but kill bacteria (which sometimes cause a more severe sinusitis). A course of antibiotics may be prescribed if symptoms are severe, or if symptoms do not settle within 7-10 days.
- Decongestant nasal sprays or drops are sometimes used. You can buy these from pharmacies. They may briefly relieve a blocked nose. However, they are not thought to shorten the duration of acute sinusitis. You should not use a decongestant spray or drops for more than 5-7 days at a time. If they are used longer than this, they may cause a worse 'rebound' congestion in the nose.
Steam inhalation is a traditional remedy, but is now not usually advised. This is because there is little evidence that it helps. Also, there have been some reports of people burning themselves trying to breathe-in steam from a kettle. However, some people say that their nose feels clearer for a short while after a hot shower.
See a doctor if symptoms do not ease within a week, or if they become worse. Also, see a doctor if you have recurring bouts of sinusitis as this may indicate an underlying problem.
Are there any complications from acute sinusitis?
Apart from chronic (persistent) sinusitis which sometimes develops from an acute sinusitis, other complications are rare. However, they can be serious. For example, infection may spread to around an eye, into bones, into the blood, or into the brain. These severe complications are estimated to occur in about 1 in 10,000 cases of acute sinusitis. They are more common with infection of the frontal sinus. Children are more prone to complications than adults. Swelling or redness of an eyelid or cheek in a child with sinusitis should be reported to a doctor urgently.