unilateral anosmia

Last reviewed 03/2021

Unilateral anosmia, or one-sided loss of the sense of smell, is less common than the bilateral lesion and is less commonly detected by the routine enquiry in a neurological examination. However, once diagnosed there are relatively few causes which ought to be investigated.

Possible unilateral causes of anosmia include:

  • head trauma
  • frontal lobe lesion - e.g. meningioma of the olfactory groove - an early manifestation.