Does nasal congestion cause loss of smell?

When the lining of the nose swells or mucus builds up, air carrying scent molecules may not reach the smell-sensitive area high inside the nose. A common cold, sinusitis, allergic rhinitis, or house dust mite allergy can cause this pattern. Smell may also change when inflammation continues after congestion improves, or when a problem affects the smell pathways for another reason.

Drink fluids, avoid smoke and other irritants, and use saline nasal rinsing only with safe, prepared water and clean equipment. If allergies are suspected, discuss allergy medication with a pharmacist or clinician. Do not use decongestant sprays for longer than the product instructions, because overuse can worsen blockage. Seek review if smell does not return as congestion settles or keeps changing.

Get urgent help for sudden loss of smell with weakness, confusion, trouble speaking, or a severe headache. Arrange prompt assessment for one-sided blockage with bleeding, facial swelling, severe facial pain, high fever, or symptoms after a head injury.

Does the pattern suggest allergy, a cold, or sinus inflammation? Is the blockage mainly on one side? Which nasal treatment is safe with my other medicines?