How long anosmia can last

Smell often returns as temporary nasal swelling or infection settles. Recovery can be slower when inflammation continues or the smell nerves have been affected, and the timing cannot be predicted from the symptom alone.

A blocked nose can prevent odour molecules from reaching smell receptors, while nerve-related anosmia can occur even when air passes freely. These mechanisms follow different recovery patterns.

A common cold, allergic rhinitis, chronic sinusitis, COVID-19, head injury, nasal growth, smoking exposure, or a medicine effect can provide clues. Some people notice distorted smells, called parosmia, as smell function changes.

Record when the problem started, whether onset was sudden, and whether nasal blockage, infection symptoms, injury, or a new medicine occurred at the same time. Once or twice a week, compare the same familiar household scents rather than repeatedly testing strong chemicals.

Smell training may support gradual recovery. Gently sample several recognisable scents on a regular routine and concentrate on the remembered smell. Do not sniff cleaning products or put fragranced liquids into the nostrils.

Until smell improves, use working smoke and gas alarms and check food dates carefully.

Contact a clinician when smell does not begin to return after a cold or nasal blockage has resolved, when symptoms worsen, or when the loss is unexplained. Earlier review is appropriate for one-sided blockage, repeated nosebleeds, persistent facial pain, or loss following a head injury.

Call emergency services for loss of smell accompanied by new facial weakness, arm or leg weakness, confusion, speech difficulty, a severe sudden headache, or serious breathing trouble.

Ask which cause matches the pattern, whether a nasal examination or smell assessment would help, and when follow-up should occur. Mention altered flavour, distorted or phantom smells, nasal discharge, facial pressure, allergy symptoms, recent infection, injury, and all medicines or supplements.