Why can Long COVID cause loss of smell?

Smell depends on receptors high inside the nose and on signals travelling to the brain. After COVID, those tissues and signals may take time to settle. Some people cannot smell at all, while others notice familiar odours smell weaker, distorted, or unpleasant.

Loss of Smell is a very common presentation of Long COVID. Nasal congestion, allergies, sinus disease, smoking, head injury, and some medicines can also affect smell, so a persistent change should be discussed with a clinician.

Reduced smell can influence taste, appetite, and safety. You may not notice spoiled food, smoke, or a gas leak as readily, even if you feel otherwise well.

Check use-by dates and food storage carefully, fit working smoke alarms, and ask someone else to check for gas or burning smells if there is any concern. Focus on food texture, temperature, and seasoning if eating has become less enjoyable.

Book a routine review if smell loss continues or affects nutrition, mood, or safety. A clinician can examine the nose, review medicines and congestion, and advise whether structured smell training or specialist assessment is appropriate.

Seek urgent care for loss of smell with sudden facial drooping, trouble speaking, severe new headache, confusion, seizure, or weakness or numbness on one side. Get medical advice promptly for persistent nosebleeds, marked facial pain or swelling, or vision changes.

Ask whether nasal inflammation or another cause could be contributing, whether smell training is suitable, and what safety measures are most useful while your sense of smell is reduced.