Olfactory impairment (dysosmia) is a variety of odor perception disorders that are manifested by an increase or decrease in olfactory function, an inability to recognize familiar aromas. The symptom occurs in inflammatory processes in the nasal cavity, craniocerebral injuries, other neurological or psychiatric diseases. To determine the root cause of the impaired sense of smell, olfactometry, ENT examination, radiography and tomography of the skull bones are performed. Until an accurate diagnosis is made, medications are not prescribed.