Loss of taste and smell: what to know

Loss of taste and smell often occur together because smell supplies much of flavour, but several causes are possible. Nasal congestion, viral illness, allergies, mouth dryness, medicines, and irritation can all change perception. Some people lose aroma while retaining basic tastes; others notice a metallic, bitter, or distorted flavour instead.

A blocked nose points toward an airflow problem, while an isolated tongue or mouth change may need an oral examination. Sudden loss of both senses can occur with respiratory infections, including COVID-19. Symptoms lasting after the initial illness may be described as part of Long COVID, but a clinician should consider other explanations before making that connection. Do not use the symptom alone to identify a diagnosis.

Treat congestion only with advice suited to you, keep hydrated, and maintain dental and tongue care. Test smoke alarms and take extra care with gas, smoke, spoiled food, and hot surfaces because smell may no longer provide a warning. Choose foods with varied textures and temperatures rather than repeatedly adding salt or sugar. Record changes and possible triggers.

Seek medical advice when the change is sudden and unexplained, continues after congestion clears, affects nutrition, or comes with repeated sinus symptoms. Urgent evaluation is needed for breathing difficulty, confusion, a severe headache, facial weakness, or other sudden neurological changes. Examination of the nose, mouth, medicines, and general symptoms can guide next steps.

Ask whether taste, smell, or both are affected; whether a nasal, oral, infectious, or medication-related cause fits; and whether testing or follow-up is needed. Mention smoking, recent illness, allergies, and any safety problems caused by reduced smell.