Quick answer. Chronic sinusitis is inflammation of the sinuses lasting more than 12 weeks, causing a persistently blocked nose, facial pressure and reduced sense of smell. It is usually manageable with sprays and rinses, though some cases need surgery.
If you have had a stuffy nose, facial heaviness and post-nasal drip that just will not clear after three months, you may be dealing with chronic sinusitis rather than one cold after another. In Singapore’s warm, humid climate, where house dust mite allergy and haze are common triggers, persistent sinus inflammation is a frequent reason people see an ENT specialist.
This guide explains what chronic sinusitis is, why it happens, how it is diagnosed and the treatment options available, from saline rinses and nasal sprays to keyhole sinus surgery. It also covers the urgent warning signs that mean you should not wait, and which specialist to see.
At a glance
| Approach | What it involves | Typically used for |
|---|---|---|
| Saline nasal rinse | Flushing the nose with sterile salt water | Everyday symptom relief and self-care |
| Steroid nasal spray | A daily anti-inflammatory spray | Reducing lining swelling and congestion |
| Allergy treatment | Antihistamines, allergen avoidance, sometimes immunotherapy | Allergy-driven sinusitis |
| Antibiotics | A doctor-prescribed course | Confirmed bacterial flare-ups |
| Sinus surgery (FESS) | Keyhole surgery to open blocked sinuses | Cases not improving with medication, or polyps |
What is chronic sinusitis?
The sinuses are air-filled spaces in the bones around your nose and cheeks. When their lining becomes inflamed and swollen, mucus cannot drain properly and the spaces feel blocked. When this inflammation lasts more than 12 weeks despite treatment, it is called chronic sinusitis (or chronic rhinosinusitis), in contrast to acute sinusitis which settles within a few weeks.
It is a common condition worldwide and a frequent complaint in Singapore, where year-round allergy triggers such as house dust mite, mould and occasional haze can keep the nasal lining irritated. It can affect adults of any age, and tends to be more troublesome in people with allergies, asthma or nasal polyps.
Symptoms and signs
Chronic sinusitis tends to cause a cluster of symptoms that linger for months. Common features include:
- A persistently blocked or stuffy nose
- Facial pressure, pain or fullness around the cheeks, eyes or forehead
- A reduced or lost sense of smell (and often taste)
- Thick nasal discharge, or post-nasal drip down the back of the throat
- A persistent cough, often worse at night, and bad breath
- Tiredness and a feeling of being generally unwell
Symptoms may flare and ease, but the underlying congestion and reduced smell usually persist between flare-ups.
Causes and risk factors
Chronic sinusitis is driven by ongoing inflammation rather than a single infection. Contributing factors include:
- Allergic rhinitis – allergy to dust mite, pollen or mould keeps the lining swollen
- Nasal polyps – soft growths that block drainage
- A deviated nasal septum or narrow sinus openings
- Repeated or poorly treated infections
- Asthma, and sensitivity to certain painkillers
- Irritants such as cigarette smoke, pollution and haze
Singapore’s humidity and high indoor dust mite levels mean allergy is a particularly common underlying driver locally.
How it is diagnosed
An ENT specialist will ask about the duration and pattern of your symptoms and examine your nose. Diagnosis may involve:
- Nasal endoscopy – a thin camera passed gently into the nose to look for swelling, pus or polyps
- A CT scan of the sinuses to map the blockage and plan any surgery
- Allergy testing (skin prick or blood test) to identify triggers
- Occasionally a swab to identify bacteria during a flare-up
The 12-week duration is part of the diagnosis, so a careful symptom history matters as much as the scans.
Treatment options
Treatment usually starts with medication and self-care, escalating to surgery only when needed:
- Saline nasal rinses to flush out mucus and irritants – simple, safe and effective for many
- Steroid nasal sprays to reduce lining inflammation over weeks
- Allergy treatment – antihistamines, allergen avoidance and sometimes immunotherapy
- Antibiotics for confirmed bacterial flare-ups, and short courses of oral steroids for polyps in some cases
- Functional Endoscopic Sinus Surgery (FESS) – keyhole surgery to open blocked sinuses when medication is not enough
Consistency matters: nasal sprays and rinses often take several weeks to show their full benefit, so it is worth persisting under your doctor’s guidance.
When to see a doctor and which specialist
See a doctor if nasal symptoms persist beyond about 12 weeks, keep returning, or are not responding to over-the-counter remedies. Seek urgent care if you develop any of these warning signs, which can point to a spreading infection: swelling or redness around the eye, changes in vision or double vision, a severe or sudden headache, neck stiffness, confusion, or a high fever. These warrant going to A&E without delay, and calling 995 if you are very unwell.
Chronic sinusitis is best assessed by an Ear, Nose & Throat (ENT) specialist, who can scope the nose, confirm the diagnosis and tailor treatment. You can find one through our directory of ENT specialists in Singapore.
Self-care that makes a difference
Day-to-day habits can ease chronic sinusitis and help your prescribed treatments work better. Saline nasal rinsing once or twice a day flushes out mucus and irritants; use sterile, distilled or previously boiled and cooled water, never untreated tap water, and clean the rinse device after each use. Because house dust mite allergy is such a common driver in Singapore’s humid climate, reducing mite exposure can help: wash bedding weekly in hot water, use mite-proof covers, keep the bedroom well ventilated and consider running the air-conditioner or a dehumidifier to lower humidity. Avoiding cigarette smoke, and staying indoors with windows shut during haze episodes, also protects the nasal lining.
Costs and subsidies in Singapore
Many people manage chronic sinusitis with a GP and pharmacy sprays. If you hold a CHAS, Pioneer Generation or Merdeka Generation card, your GP can provide subsidised care and, where clinically appropriate, a subsidised referral to a public Specialist Outpatient Clinic for ENT assessment. If sinus surgery (FESS) is recommended, inpatient or day-surgery costs may be partly covered by MediSave and MediShield Life; check eligibility with your hospital rather than relying on a single quoted price.
Common questions
Will I need surgery?
Most people do not. Surgery is usually considered only when medication and rinses have been tried properly and symptoms persist, or when nasal polyps or structural blockage are present.
Why do nasal sprays seem not to work?
Steroid nasal sprays often take several weeks of regular, correct use to show their full effect, and they need consistent daily use rather than only when blocked.
Related guides
- Best ENT Clinics in Singapore — our editorial shortlist
- ENT clinics directory
- Labyrinthitis
- Perforated eardrum
- Glue ear
- Vocal cord nodules
- Uterine prolapse
Sources
- HealthHub Singapore – Sinusitis
- NHS – Sinusitis (sinus infection)
- Mayo Clinic – Chronic sinusitis
- SingHealth – Sinusitis
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