Anosmia

Professor Thomas Havas

Are you experiencing Loss of Smell (Anosmia)? Talk to us!

We would like to help you understand why Anosmia is happening to you. However, doing online research is not an effective way to fix this problem. Make sure you will come to see the best ENT specialist!

Professor Thomas Havas is the current Chairman of the Department of Otolaryngology Head and Neck Surgery at Prince of Wales and Sydney Hospitals. He established the first integrated nose clinic in Australia since 1980's. Willing to see him? Give us a call or use the booking form after you get a referral letter from your local doctor.

Anosmia (Loss of Smell)

Loss of Smell

Loss of smell is called anosmia. The sense of smell largely determines the flavour of food and beverages and serves as an early warning system for the detection of environmental hazards. This primary sensory system contributes significantly to one’s quality of life allowing for the full appreciation of flowers, perfume, spices and a vast array of food and beverages. Thus it is little wonder that loss or alteration of smell sensation is of considerable significance to patients, particularly those dependent on their sense of smell for their livelihood or safety.

Causes of Anosmia

Head injury

  • The severity of head injury can be from major to minor. Damage to the olfactory bulb can occur with or without damage to the cribriform plate. Alteration of the sense of smell is associated with approximately 10% of major head injuries.

Surgery

  • Cranial surgery and intranasal sinus or transphenoidal surgery can be associated with loss or alteration in sense of smell.

Infection

  • Rhinosinusitis can damage the olfactory neuroepithelium. Damage is more likely with chronic sinus infection than with an acute infection.
  • Long term use of nasal sprays particularly sympathomimetic amines have been shown to be associated with alteration in sense of smell.

Medical conditions

  • Kallmann’s Syndrome is a genetically determined syndrome associated with failure to develop olfactory bulbs resulting in congenital anosmia.
  • Psychological/psychiatric conditions can affect smell perception, for example depression, hysteric conversion reactions, and schizophrenia.
  • Meningitis, especially in infancy.
  • Temporal lobe epilepsy.
  • Sjogren’s Syndrome.

The sense of smell deteriorates with age.

Medication

  • Long term use of nasal sprays.
  • Antibiotics such as Metronidazole, Ciprofloxacin or Cefuroxime.
  • Zythromax
  • Drugs such as Amitriptyline.
  • ACE inhibitors.
  • Radiation therapy of the head and neck.

Chemicals

  • Chemical exposure can cause mechanical damage to the olfactory epithelium.
  • Cleaning agents such as ammonia with a strongly alkaline pH are very toxic to neuroepithelium.
  • Irritants – cigarette smoke interferes with one’s ability to smell essentially due to drying of the nasal mucosa and also direct toxic damage to the neuroepithelium.

Sinus problems. Other intranasal causes;

  • Deviated nasal septum.
  • Crooked nose.
  • Significant nasal obstruction due to allergic or inflammatory conditions.
  • Benign nasal tumours such as nasal polyps.
  • Malignant nasal tumours.
  • Some pituitary tumours extending into the nose.

Anosmia Cure

Treatment of altered sense of smell depends obviously on the diagnosis.

Following a viral upper respiratory tract infection without intercurrent persisting rhinosinusitis; the required treatment is nasal decongestants ± trial of oral steroids.

Chronic sinusitis associated with altered smell; long course of appropriate antibiotics, nasal decongestants, normal saline douches. A pulse of oral steroids is an accurate predictive test. If smell returns while on steroids prospect for the return of smell is good. If smell does not return with a pulse of oral steroids the prospect of return to smell is poor.

Structural abnormalities in the nose associated with altered smell are usually treated surgically. The most common surgeries are Nasal Septal Reconstruction plus or minus judicious Endoscopic Sinus Surgery.

Tumours in the nose associated with altered smell; the most common nasal tumours are benign nasal polyps and again steroid pulse predictive index is high. Appropriate management for nasal polyposis usually involves judicious surgery associated with lifelong follow-up and appropriate adjuvant medical therapy.

Post traumatic hyposmia or anosmia is usually associated with a poor outcome. Correction of cranial cribriform plate fractures usually does not lead to improvement and/or return of sense of smell.

Anosmia associated with allergy; again the steroid predictive index test is accurate. Appropriate management of the nasal allergy by way of intranasal low dose water based steroid sprays/decongestants/normal saline douches plus or minus appropriate desensitisation helps improve penetration to the area of the olfactory cleft and if the steroid predictive test indicates the olfactory neuroepithelium is intact long term results in terms of restoration of sense of smell are good.

Idiopathic anosmia, that is to say the loss or alteration of smell in adult life, is not associated with mechanical problems in the nose, intercurrent rhinosinusitis and/or allergy. It is usually associated with a poor outcome. Zinc, copper and other trace elements have occasionally been used. The evidence of their efficacy is weak.