Health Library

Smell and Taste Disorders

What are smell and taste disorders?

The most common smell and taste disorders are:

  • Anosmia. Loss of sense of smell
  • Ageusia. Loss of sense of taste
  • Hyposmia. Reduced ability to smell
  • Hypogeusia. Reduced ability to taste sweet, sour, bitter, or salty things

In other disorders, odors, tastes, or flavors may be misread or distorted. They may cause you to detect a bad odor or taste from something that is normally pleasant to taste or smell. These disorders can affect quality of life. They may also be a sign of underlying disease.

Problems with taste and smell can suggest certain health problems, such as:

  • Obesity
  • Diabetes
  • High blood pressure
  • Poor nutrition
  • Nervous system diseases, such as:
    • Parkinson's disease
    • Alzheimer's disease
    • Multiple sclerosis

What causes smell and taste disorders?

Some people are born with these disorders, but most are caused by:

  • Illness (for example, cold or flu, sinus infection, and allergies)
  • Head injury
  • Hormone changes
  • Dental or mouth problems
  • Nasal polyps
  • Exposure to certain chemicals
  • Certain medications
  • Exposure to radiation therapy for head or neck cancer
  • Cocaine snorted through the nose
  • Cigarette smoking

What are the symptoms of smell and taste disorders?

Symptoms can range from the not being able to smell or taste at all to the reduced ability to smell or taste specific things that are sweet, sour, bitter or salty. In some cases, normally pleasant tastes or smells may become unpleasant.

How are smell and taste disorders diagnosed?

Along with a complete medical history and physical exam, other test may include:

  • Measuring the lowest strength of a chemical that a person can recognize
  • Comparing tastes and smells of different chemicals
  • "Scratch and sniff" tests
  • "Sip, spit, and rinse" tests where chemicals are applied to specific areas of the tongue

How are smell and taste disorders treated?

Your health care provider will figure out the best treatment for you based on:

  • How old you are
  • Your overall health and medical history
  • How sick you are
  • How well you can handle specific medications, procedures, or therapies
  • How long the condition is expected to last
  • Your opinion or preference

Treatment may include:

  • Stopping or changing medications that contribute to the disorder
  • Correction of the underlying medical problem
  • Surgical removal of obstructions that may be causing the disorder
  • Counseling
  • Quitting smoking

What are the complications of smell and taste disorders?

While both smell and taste disorders affect quality of life, smell disorders can be dangerous. They damage your ability to detect such things as:

  • Fire
  • Poisonous fumes
  • Leaking gas
  • Spoiled food and beverages

Taste disorders can affect nutrition and lead to weight loss and malnutrition. It can also harm the immune system and worsen other medical conditions.

Key points

  • The loss of the senses of smell and taste are the most common smell and taste disorders.
  • Other disorders include the reduced ability to smell or taste specific substances that are sweet, sour, bitter or salty.
  • For some people, normally pleasant tastes or smells may become unpleasant.
  • Treatments for smell and taste disorders often include treating the underlying cause.
  • Smell and taste disorders can affect quality of life and should be treated.

Next steps

Tips to help you get the most from a visit to your health care provider:

  • Before your visit, write down questions you want answered.
  • Bring someone with you to help you ask questions and remember what your provider tells you.
  • At the visit, write down the names of new medicines, treatments, or tests, and any new instructions your provider gives you.
  • If you have a follow-up appointment, write down the date, time, and purpose for that visit.
  • Know how you can contact your provider if you have questions.