Who is this information for?
This information is for patients, families and carers of patients with anosmia.
What is anosmia?
- Anosmia is the complete loss of sense of smell; hyposmia is a reduction in sense of smell. The loss may be temporary or permanent. Anosmia does not usually have a serious cause, but can have a profound effect on a person for life. People with anosmia may not be able to fully taste food.
- Smell and taste are often both affected as most of our taste sensation comes from our sense of smell. Taste is actually detected by receptors on our taste buds, which are found on our tongue and in our mouths. Information about what we taste is collected by these taste receptors and sent to the brain. However, the flavour of our food is largely due to its smell.This is detected by smell receptors in the lining of the nose; the smell of food travels from the back of the mouth into the back of the nose.
What causes anosmia?
- Nasal & sinus disease eg rhinitis, chronic rhinosinusitis, nasal polyps (25%)
- Upper respiratory tract infections eg cold, flu (20%)
- Head injury including whiplash (15%)
- Neurological causes eg Parkinson’s disease, Alzheimer’s (2-5%)
- Congenital anosmia – born with no sense of smell (1%)
- Other causes eg age-related, thyroid disease, liver disease, diabetes, smoking (5-10%)
- Idiopathic – unknown cause (25%)
How is anosmia diagnosed?
- A healthcare practitioner will ask you about your current symptoms, medical history and examine your nose.
- Depending on the findings, your health care provider may perform one or more of the following tests:
- Computerised tomography (CT) scan of the sinuses
- Magnetic resonance imaging (MRI) of the smell area in the brain
- Blood tests
What safety precautions should I take if I have anosmia?
- Have functioning smoke alarms in the homes – you cannot smell smoke
- Carefully label food with expiration dates – you cannot smell spoiled food
- Check that gas cookers and barbecues are turned off properly – you cannot smell gas leaks
- Read labels on chemicals like kitchen cleaners and insecticides
- Ensure that electrical appliances are used as per the recommendations and are turned off when not in use
- If your sense of smell is required as part of your occupation, you should discuss this with your employer or supervisor
How is anosmia treated?
Treatment of anosmia depends on the cause. If the loss of smell occurs with a cold, allergy or
sinus infection, it will usually clear up on its own although may take several weeks/months.
Treatments that may help to resolve anosmia caused by nose & sinus conditions include:
- Steroid tablets or nasal sprays
- Antihistamines (for allergic rhinitis)
- Antibiotics (for bacterial infections)
- Reducing exposure to nasal irritants and allergens
Loss of smell caused by nasal obstruction can be treated by removing whatever is obstructing
the nasal passage. This may include:
- An operation to removal nasal polyps (sinus surgery) or to straighten the nasal septum
- Cessation of smoking
- Smell training (see “Further information” below)
- In some cases there is no treatment available
- Try and maintain nutrition levels by weighing yourself regularly and setting reminders for
- Try and improve the sense of taste: adding concentrated flavouring agents to food or
cooking with ingredients that stimulate taste buds that are more colourful or textured may
restore interest in food
Concerns or questions?
You can contact your ENT Specialist at the Melbourne ENT Group (MEG):
Your GP is also the best contact for ongoing care and concerns.