Loss or Reduction of the Sense of Smell

Why does the sense of smell matter?

Smell protects us from dangers such as smoke, gas leaks, and spoiled food, and gives us enjoyment in eating. Most of what we call "taste" actually comes from smell.

This is why many people who lose their sense of smell feel that food has become tasteless.

What are the symptoms?

Reduced or lost sense of smell
Changed taste or loss of enjoyment in eating
Smelling odors that aren't there
Smelling odors differently or as unpleasant, often occurring during recovery

What are the causes?

Chronic sinusitis and nasal polyps
Viral infections, such as colds, flu, and COVID-19
Allergic rhinitis
Head injuries
Aging
Smoking
Certain medications
Occasionally, an early sign of certain neurological conditions, such as Parkinson's disease

How is it diagnosed?

Questions about when the problem began and its possible causes.
Nasal endoscopy.
Smell tests using specific odors.
Sinus imaging or MRI may be requested depending on the case.

What are the treatment options?

Treating the cause

When sinusitis or polyps are present, smell often improves with steroid treatment or surgery.

Smell training

One of the most well-proven treatments for smell loss after viral infections. It involves smelling a set of different scents daily with focused attention, for several months.

Patience

Smell often improves gradually after viral infections in many patients, and this can take months to a year or more.

Insulin

Studies show improvement in some cases with sessions applying insulin to the olfactory cleft; ask your doctor whether this option is suitable for you.

Platelet-rich plasma injections

Studies show improvement in a significant proportion of cases after several sessions of platelet-rich plasma injections into the olfactory cleft; ask your doctor whether this option is suitable for you.

How do I practice smell training?

Choose 4 different scents, such as: rose, lemon, clove, and mint or coffee.
Gently smell each scent for about 20 seconds.
Focus and picture the scent as you smell it.
Repeat this twice daily for at least 3 months.
You can change the scents after a period of time.

Remember: the scents used for training should be safe — never use chemicals or cleaning products.

Safety tips

Install smoke and gas detectors at home, and check them regularly.
Check food expiration dates, and don't rely on smell.
Turn off the gas properly after cooking.
Ask a family member to check smells around the home or on clothing when needed.
Don't overuse salt and sugar to compensate for taste.

When should I see a doctor?

If reduced smell persists more than two weeks after a cold.
If accompanied by persistent one-sided obstruction, discharge, or bleeding.
If it begins gradually without a clear cause.
If accompanied by changes in memory or movement.

Go to the emergency room if:

You lose your sense of smell after a strong head injury, with headache, vomiting, or drowsiness
Accompanied by clear, watery fluid running from the nose
Accompanied by sudden weakness or numbness in the face or limbs

Remember

Reduced smell is common and has many treatable causes.
Smell training is helpful after viral infections.
Smoke and gas detectors are essential for your safety.
One-sided nasal symptoms need examination.

This information is for health awareness and education, and does not replace a doctor's consultation or direct medical assessment.

Prepared by: Saudi Society of Otolaryngology–Head & Neck Surgery · Version 1.0 · Last reviewed: May 2026 · saudiorl.com