Smell and taste disorders in primary care.

Authors: Malaty J, Malaty IA.



Smell and taste disorders are difficult to diagnose due to the large number of possible aetiologies. Gustatory and olfactory dysfunctions are implicated in loss of appetite, unwanted weight loss, malnutrition and reduced quality of life, especially in older adults. The most relevant and persistent deficiencies in the gustatory organs of elderly patients are: ageusia, phantom ageusia and hypogeusia. On the other hand, the deficiencies affecting smell are: anosmia, hyposmia and parosmia. To diagnose, evaluate and advise treatment for these disorders it is first necessary to perform the following three clinical processes:

  • A review of the patient’s history. The treatment must be performed according to the type of disorder that is detected. Here, the patient´s lifestyle is relevant.
  • A physical examination. This analysis can derive specifically towards the olfactory, taste or neurological system.
  • Certain diagnostic tests. Briefly, it would be nasal endoscopy and computerized tomography.

The treatments are applied according to the specific causes that gave rise to the olfactory and taste disorders of the patient. For example, it is noted that sinus conditions are responsible for 52% to 72% of olfactory disorders in certain population groups. The pollinosis (hay fever related to allergies) is a common disorder, and depending on the applied treatment, the patient will take more or less time to recover. Among the available treatments, nasal steroids remains the most common method to solve loss of olfactory sensitivity. According to the authors, it should be applied in conjunction with a twice-a-day exposure of four scents (eucalyptus, citronellal, eugenol and phenylethyl alcohol). Similarly, the therapy must be adapted to those affected by neurodegenerative diseases, such as Parkinson’s or Alzheimer’s disease, among others.

On the other hand, brain and head injuries (closed lesions and cortical trauma) can produce alterations in these sensitive organs, causing damage to the olfactory nerve due to fractures of the cribriform plate. Likewise, the deficiency of smell and taste caused by smoking and consumption of certain drugs is noted. However, the disorders caused by the drugs are temporary and transient, resolving three months after cessation of the medication. Currently, it is known that 95% of perceived disorders in taste are caused by olfactory loss rather than taste loss. In conclusion, the factors hamper improvement through olfactory treatment are the severity of the disorder, the long duration of symptoms, the patient’s advanced age and smoking, highlighting that women tend to have a better prognosis than men.