Anosmia

This code represents the complete loss of the sense of smell. It indicates an inability to detect odors, which can be a symptom of various underlying conditions affecting the olfactory system.

Use this code when documentation explicitly states a patient has anosmia, meaning a total absence of the sense of smell. This applies whether the anosmia is acute, chronic, or of unknown etiology, and when no more specific cause is yet identified or coded.

• Differentiate from hyposmia (R43.8), which is a reduced sense of smell, not a complete loss.
• Always code any underlying cause of the anosmia first, if known and documented (e.g., head injury, nasal polyps).
• If the anosmia is drug-induced, also code the adverse effect of the drug.