Parosmia is a smell disorder. In this disorder the part of brain that recognizes sense of smell is not able to perceive the odor of substances. In fact the odor of a substance is perceived as something offensive by the olfactory lobe of the brain which in reality is not present. Thus, in parosmic patients even the natural pleasant odor of a substance is perceived to be offensive and foul. Many patients recognize the natural odor similar to fecal odor, chemical, burning, or rotten.
People suffering from parosmia are distressed in their day to day life as they are not able to distinguish between aromas of different food products.Upper respiratory tract infection, traumatic head injury, parkinson’s disease, sinusitis are some of the causes of parosmia. There is no specific treatment of parosmia, but after few days or weeks problem decreases on its own.
Symptoms Of Parosmia
Patient suffering from parosmia is unable to identify the correct smell of a substance. As a result he finds trouble eating food as he is not able to differentiate between food flavors. Even pleasant flavor of food smells foul and altered.
Persistent foul smell is the most frequent complain of patient suffering from parosmia. The smell makes him sick.For him the smell of any substance is perceived to be similar to fecal odor or that of a rotten flesh. For example patient perceives smell of an orange as unpleasant and burning.
What Are The Causes Of Parosmia?
The inside of nose is lined with olfactory sensory neurons (OSN). These are specialized cells in the lining of mucus membrane of the nose. These cells are receptor cells that receive particular smell in the air and relay the sensation to the center of brain called olfactory lobe. Here the smell perceived by the ONS is evaluated.
However, when olfactory sensory neurons in the nose are damaged it signals the brain of distorted smell that is not a natural odor in reality. It leads to a disorder called parosmia. Here are some important causes of parosmia.
- Parosmia is frequently associated with upper respiratory tract infection. Patients with chronic rhinitis, sinusitis, sore throat, bronchitis are known to suffer from parosmia as their sense of smell is distorted due to damage to the OSN.
- Injury to head, especially to the olfactory bulb in the brain which is responsible for differentiating various smells. Damage to olfactory center in the brain results in conditions such as parosmia.
- Chronic smokers are known to suffer from parosmia. Smoking is known to cause sinusitis and various other respiratory tract illnesses. It damages the sensory cells in nose that are responsible for transmission of odor to the brain.
- Smoke of harmful chemicals and acids is also detrimental for sensory cells in nose. Once damaged it can lead to distorted smell.
- Medication, particularly long term use of antibiotics is responsible for impairment is ability to smell.
- Neurological diseases such as Parkinson’s disease, Alzheimer disease, and seizures can damage the area of brain that processes and evaluates sense of smell.
Treatment For Parosmia
There is no specific cure available for parosmia. Fortunately the symptoms lessen over a period of time. In some patients it may take years to decrease. A drug levo dopamine is used by some health care practitioners, but there is no sure evidence of its success.
Some patients who are frustrated with the problem which has been since many years often opt in destroying the olfactory bulb with surgery.