What should you know about loss of smell sensation?

The medical term for a complete loss of smell is anosmia. A reduced sense of smell is sometimes called hyposmia. Because smell contributes to flavour, food may seem bland when your nose cannot detect aromas.

A blocked or inflamed nose can prevent scent molecules from reaching the smell receptors high inside the nasal passages. Allergic rhinitis, a common cold, and chronic sinusitis can cause this type of change, often alongside sneezing, discharge, facial pressure, or reduced nasal airflow.

Viral infections, including COVID-19, can also alter smell even when nasal blockage is not prominent. Some people notice distorted smells or phantom odours while the sense is returning. Persistent symptoms after an infection can occur as part of Long COVID.

Smell loss can reduce awareness of smoke, gas, spoiled food, or other hazards. Check alarms, follow food-safety dates, and ask someone else to assess a suspected gas leak or spoiled food rather than relying on smell alone.

Notice when the change began and whether it affects one or both sides of the nose. Record associated symptoms such as congestion, fever, facial pain, headache, nasal bleeding, or a recent respiratory infection.

Saline nasal rinsing may help clear mucus when congestion is present, but use sterile, distilled, or previously boiled and cooled water with a clean device. Avoid putting irritants or unapproved oils inside the nose. A clinician or pharmacist can advise whether treatment for allergy or sinus inflammation is suitable for you.

Arrange a medical review if the change does not improve, keeps returning, or affects eating, safety, or daily life. Assessment may include an examination of the nose, a review of medicines and recent illness, and a simple smell test.

Seek urgent medical help for smell loss with sudden weakness, facial drooping, trouble speaking, confusion, severe headache, or a head injury. These symptoms can signal a problem that needs prompt assessment.

Contact a clinician promptly for one-sided blockage, repeated nosebleeds, severe facial swelling or pain, vision changes, or symptoms that are worsening. Arrange routine care for persistent or unexplained loss, especially if it began without a cold or allergy symptoms.

Ask: Could congestion, allergy, infection, a medicine, or sinus inflammation explain the change? Should I have a nasal examination or smell test? Which nasal treatments are appropriate for me, and how should I protect myself from smoke, gas, and spoiled food while smell is reduced?