Waking up regularly with a nasal congestion, leaky nose and throbbing headache is no fun.
If you suffer from sinus problems, you have probably turned up at the office with tissues shoved up your nostrils, feeling miserable and uncomfortable.
What is causing your nasal woes and is there a way to get rid of them for good?
This is what experts say.
Understanding your sinus
It is common for people to refer to a persistent blocked or runny nose as "having sinus".
"Actually, the term sinus refers to an air cavity around the nose," said Dr Dharambir S Sethi, an ear, nose and throat specialist at Mount Elizabeth Novena Hospital.
We have four pairs of these air cavities - in the forehead bone, cheekbones, between the eyes and at the back of the nose almost in the centre of the head.
Your sinuses are lined with a membrane that produces mucus, which moistens the tissues in the nasal passages and helps trap and flush out dirt and harmful microbes.
Sinusitis occurs when this lining becomes inflamed.
"Inflammation may be due to viral infection, bacterial infection, fungal infection, smoking or allergies," said Dr Sethi.
Dr Ker Liang, head and neck surgeon at the department of otolaryngology at National University Hospital, added: "Inflammation then leads to nasal obstruction."
The swelling membranes can block your sinuses, cause facial pain and produce coloured nasal discharge.
Other symptoms include fever, persistent headache, chronic cough, ear pain and reduced sense of smell.
Multiple kinds of sinusitis
"If the infection lasts for less than four weeks, it is defined as an acute infection. When it persists for more than 12 weeks, it is considered a chronic infection," said Dr Sethi.
Most cases are acute and are caused by bacterial or viral infection, such as the flu virus. Up to 40 per cent of patients recover on their own within two weeks.
Dr Ker said: "If no improvement is seen after two weeks, patients will be given a course of antibiotic therapy to combat the infection."
Two or three courses may be required. Chronic infections that last for more than 12 weeks are usually due to allergies, structural problems within the nose or issues relating to the immune system.
The World Allergy Organisation Journal says one in 10 people suffer from chronic sinusitis.
Chronic sinusitis can result in fatigue, dental pain and cough, on top of the usual symptoms.
Multiple courses of antibiotic therapy may be ineffective in this case.
And if the infection worsens and spreads to the eye or the brain, surgery may be necessary.
Is it really sinusitis?
You may feel that your recurrent nasal congestion, runny nose and head pain are a result of chronic sinusitis but doctors say more often than not, it is not the case.
"If you wake up regularly with a dripping or congested nose, it is more likely you have allergic rhinitis," Dr Ker said.
Allergic rhinitis refers to hypersensitivity of the nose to environmental allergens such as dust mites, animal fur or haze - one in five people here have it.
The symptoms are similar to sinusitis, including nasal congestion, runny nose, nasal itch and sneezing. But unlike chronic sinusitis, there is no facial pain or dysfunction in one's sense of smell.
Instead, eye irritations, such as itchiness, tearing and redness may plague you.
Dr Ker noted another distinction: "Patients with allergic rhinitis produce a clear, dripping nasal discharge, while those with chronic sinusitis produce a thick yellow or green discharge."
As allergic rhinitis causes the tissues in your nose to become inflamed, it can also cause your sinuses to become inflamed, resulting in sinusitis.
Your doctor can prescribe a nasal sinus wash, a saline solution used to flush out mucus and allergens, as well as antihistamines and intra-nasal steroid sprays, which stop inflammation.
Surgery for chronic sinusitis safe but best avoided for kids
Patients with chronic sinusitis that does not respond to antibiotics could have mucous cysts, benign tumours or nasal polyps, which are small non-cancerous growths, in the nose or sinuses, said Dr Dharambir S Sethi, an ear, nose and throat specialist.
Or it could be caused by a fungal infection, which cannot be treated with antibiotics.
Surgery may be needed, but it is not as scary or agonising a procedure as you might think.
Here is what can be done.
Functional endoscopic sinus surgery (Fess)
"The aim of Fess is to remove diseased mucosa and bone from the sinuses. This allows the mucus to clear and promotes healing of the mucous membrane," said Dr Ker Liang, a head and neck surgeon.
Performed under local or general anaesthesia, an endoscope is inserted into the nose so the surgeon can see the nasal tract and remove diseased tissues.
No external cuts or incisions are made; any infected mucus in the sinuses is also flushed out. Pain is minimal, said Dr Sethi.
He said: "But it can hurt more if the operation involves all the sinuses, and concurrent procedures."
The minimally invasive day surgery costs between $620 and $8,465 at public hospitals.
Also read: Unblocking hypersensitive noses
In this option, a balloon dilation catheter is inserted into the sinus and inflated.
"The objective is to widen the outflow tract of the sinus without having to remove any tissue," said Dr Sethi.
While this is less painful and results in a quicker recovery, it is suitable in only some situations, such as when the cause of sinusitis is isolated within a single sinus.
Septoplasty and turbinoplasty
In septoplasty, the cartilage between your nostrils is realigned, and in turbinoplasty, parts of the walls in your nose are removed.
These are done to improve airflow and relieve nasal obstruction and may be more painful.
Also read: 5 natural remedies for the cold and flu
Is surgery worth it?
Endoscopic sinus surgery is safe and the risk of major complications, such as damage to the eyes or blood vessels, is extremely low, at about 2 per cent.
But Dr Sethi noted it is best avoided for children as there is evidence it may interfere with the growth of the facial skeleton.
Recovery takes just one to two weeks.
You can expect a few nose bleeds, blood-stained saliva and crusting or scabs that form on the mucous membrane as it heals during this period.
For the next three to six weeks, doctors will monitor the healing closely and help with post-operative care.
That includes sucking out blood clots or prescribing antibiotics to deal with any infections that may occur.
"But surgery does not immunise you against the recurrence of sinusitis," said Dr Ker.
"Although, you are more likely to recover from future infections completely and quickly with medication."
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