When does loss of smell happen with COVID?

COVID-19 can affect smell-sensing cells and the way smell signals are processed. Some people notice that food tastes different because flavour depends partly on smell. The change may be reduced smell, a complete inability to smell, or distorted smells. A blocked nose from a common cold, allergic rhinitis, or chronic sinusitis can also reduce smell, so the symptom alone cannot identify the cause.

Follow current local guidance about testing, staying home when unwell, and limiting close contact. Record when the change started and whether congestion, fever, cough, or a sore throat appeared. Avoid relying on smell to detect smoke, gas, or spoiled food while it is reduced; check alarms and ask someone you trust to confirm food safety. Seek medical advice if the loss persists, returns repeatedly, or affects eating and daily activities.

Get urgent help for trouble breathing, chest pressure, new confusion, fainting, or difficulty staying awake. Arrange prompt medical assessment for severe dehydration, worsening illness, or a new neurological symptom. Persistent loss of smell after the acute infection may fit with Long COVID, but other causes still need consideration.

Ask whether testing is appropriate, whether nasal congestion could explain the change, and when follow-up is needed if smell does not return. You can also ask how to protect yourself from household hazards while your sense of smell is impaired.