Can nasal congestion cause loss of smell?

Smell depends on air carrying scent molecules to a small area high inside the nose. A cold, allergic rhinitis, or sinus inflammation can narrow the nasal passages and cover that area with swelling or mucus. Food may also seem less flavoursome because smell contributes strongly to flavour. Smell usually improves as the blockage settles, but ongoing congestion can point to persistent inflammation, nasal polyps, or another cause. A change in smell can also occur without a blocked nose, so the pattern and timing matter.

Drink fluids, rest, and use gentle saline nasal rinsing if it is suitable for you; use sterile or previously boiled and cooled water for a home rinse. Avoid inserting objects into the nose. If allergy symptoms are prominent, a pharmacist or clinician can explain appropriate allergy treatment. Do not use decongestant sprays beyond the recommended short period, as overuse can worsen blockage. Notice whether smell returns as breathing clears and record other symptoms.

Book an appointment if loss of smell persists after congestion improves, keeps returning, or occurs without nasal symptoms. Seek prompt care for severe facial swelling, severe headache, vision changes, confusion, or a high fever with worsening illness. A clinician may examine the nose, review medicines and allergies, and decide whether further assessment is needed.

Ask whether your symptoms fit a cold, allergy, or sinus problem, which nasal treatment is appropriate, and when persistent smell loss needs specialist assessment. Mention any recent injury, new medicine, or change in taste.