Types of smell loss

Most people become aware of smell loss when they lose the ability to taste food. In most cases, smell and taste will return normally after a couple of weeks. If smell and taste don’t return after three weeks, make an appointment to discuss this with a doctor. We have a ‘talking to my doctor’ document which you can take with you to your appointment.

What causes smell loss?

  • Viral infection, such as cold, flu or Covid-19.
  • Head trauma
  • Allergies, such as hay fever.
  • Nasal polyps, benign growths in the tissues lining of your nose.
  • Ageing
  • Some medications
  • Radiation treatment for head and neck cancers.
  • Exposure to dangerous chemicals such as pesticides or solvents.
  • Abuse of cocaine and other drugs inhaled through the nose.
  • Smoking
  • Poor air quality
  • Some neurodegenerative conditions such as Parkinson’s disease, Alzheimer’s disease, or brain tumours.

Definitions of smell loss 

  • Anosmia is a complete absence of the sense of smell.
  • Acquired anosmia is a result of illness or injury. People with congenital anosmia are born without smell.
  • Hyposmia is a reduced sense of smell. 
  • Idiopathic smell loss is when the cause of anosmia is not known.
  • Normosmia a normal sense of smell.
  • Parosmia is a distorted sense of smell.
  • Phantosmia is when you experience smells that aren’t there. 
  • Ageusia is the absence of gustation (true taste: salty, sweet, sour, bitter and savoury (umami). 
  • Dysgeusia is distorted gustation, for instance a metallic taste
  • Flavour is a combination of smell and taste, but it is mostly smell that enables us to enjoy flavour.