
Have you lost your sense of smell? Hyposmia is the loss of the sense of smell and may happen for many reasons. These range from the common cold or flu, to sinus infections and nasal tumours. At ENTcare specialist clinic in Singapore, many patients have lost their sense of smell because of nasal allergy, polyps and sinus infections. Up to 80% of your sense of taste actually depends on your sense of smell.
So hyposmia can be devastating as it could mean the loss of someone's job in the F&B industry in Singapore. Just think of all those people who depend on their good sense of smell e.g. chefs, sommeliers and those in the food import business. Therefore, people who work daily with gas and other toxic substances also depend on their sense of smell to stay safe. Can you imagine if you suddenly couldn't smell anything toxic in a factory? Your life would be at risk!
In about 40% of anosmia cases in Singapore, the loss of your sense of smell is due to a viral infection. Viral infections lead to swelling and inflammation of the olfactory nerve which controls the sense of smell. Subsequently, this results in soft tissue swelling inside the nose with increased mucus production. So all the excess tissue swelling and mucus block the passage of the odour molecules to the top of the nose, where the olfactory/smell nerve endings are located. Fortunately, in most cases like this, your sense of smell usually returns once your viral infection is better.
Sometimes, the common cold or the flu can lead to more severe sinus infections. Then this leads to thick yellow purulent nasal discharge, facial pain and headaches with fever. You may also suffer a blocked nose during a sinus infection. So you will probably need a course of strong antibiotics to treat the sinus infection. Saline rinses, nasal steroid sprays and antihistamines can be helpful in treating the sinus infection to help you recover your sense of smell.
Nasal polyps are enlarging growths inside your nose. They look like yellow or grey grapes. Nasal polyps may be due to nasal allergy (allergic rhinitis) but sometimes, they may be caused by a fungal infection. If they grow too big, they become very difficult to breathe through your nose. Then they may cause recurrent sinus infections. Rarely, some nasal polyps may be pre-cancerous. So you should always have your nasal congestion checked properly by a top ENT specialist in Singapore. The ENT specialist will use a special camera (naso-endoscope) to examine your nose thoroughly.
At our top ENT specialist clinics in Singapore, nasal allergies (allergic rhinitis), sinus infections and nasal polyps are all easily treatable causes of anosmia. We usually try a course of medications first but some patients may need surgery if medications fail to help. A CT scan of your sinuses and sometimes, an MRI scan of the brain can investigate why you might have lost your sense of smell and to help plan for surgery.
Did you know about this latest treatment to help regain your sense of smell? A recent development in treating loss of the sense of smell involves injecting Platelet-Rich Plasma (PRP) directly into the olfactory cleft. This is a special area high up in your nose. The PRP injection aims to stimulate nerve regeneration and heal damaged tissues. The PRP actually comes from a sample of your own blood taken in the clinic so it is very safe.
After numbing the nose with local anaesthesia, we inject the PRP into the area of the olfactory nerve (the "cleft"). PRP is emerging in more studies as the next novel technique to help recover your sense of smell.
We usually perform PRP for the olfactory nerve in patients who have already had little success with steroids, sinus rinse and decongestants. Your CT or MRI scan of the sinuses and brain should also not show any other cause of your hyposmia.
The Process: A sample of blood is taken from your arm and spun in a centrifuge machine to separate the platelet-rich plasma (PRP).
The Procedure: After numbing the nose, the PRP is carefully injected into the nose where the nerve endings of the olfactory nerve lie.
So after each injection, you can continue your usual activities for the rest of the day.
Patients usually have 3 injections, each taking place about 4 weeks apart. Everything takes place in the clinic and is quite comfortable.
It can take several months for the nerve endings of your olfactory nerve to regenerate. One study done recently at The Mayo Clinic reported that up to 87% of patients noticed improvement about a year after undergoing PRP treatment for their olfactory nerves.

Dr Annabelle Leong 梁翠娟
Senior Consultant ENT Surgeon
MBBS (Hons) (London), BSc (Hons);
DOHNS, MRCS (England), FRCS ORL-HNS (England)
Dr Annabelle Leong is a senior consultant ENT surgeon with more than 25 years of experience across the United Kingdom, Canada and Singapore. From childhood ENT concerns to hearing, balance and sleep problems in adults, she provides care across a broad range of ear, nose and throat conditions.
Known for being a patient and attentive listener, Dr Annabelle takes a sensible, holistic approach to care, considering the wider picture before recommending treatment. She favours conservative options where appropriate, with surgery considered when clinically indicated and appropriate for the patient’s overall care.