Can congestion cause loss of smell?

Smell depends on air carrying odor molecules to specialised tissue high inside the nose. Swelling from a common cold, allergic rhinitis, or sinus inflammation can reduce that airflow. A blocked nose may therefore make food seem less flavourful as well. COVID-19 can also alter smell, sometimes without major nasal blockage, and some people notice changes that continue after the initial illness. Loss of smell can be partial or complete, and the pattern and timing help a clinician consider the cause.

Treat nasal blockage gently with fluids, rest, and saline spray or rinse prepared according to product directions. Avoid inserting objects into the nose and avoid smoke or strong irritants. If allergies seem to trigger the congestion, a pharmacist or clinician can help select a suitable treatment. Do not repeatedly use a medicated decongestant spray beyond its label advice, because overuse can worsen blockage. Keep food safety in mind when smell is reduced: check dates and use sight and texture rather than smell alone.

Arrange an assessment if smell does not return as the congestion clears, if the change is sudden without a blocked nose, or if it follows a head injury. Seek urgent help for trouble breathing, severe facial swelling, confusion, or new neurological symptoms. A clinician may examine the nose, review recent infections and medicines, and decide whether further testing is needed.

Ask whether the pattern fits congestion, allergy, sinus disease, or a recent viral infection; whether any medicine could be contributing; and how long to monitor recovery before review.