Dysosmia (Lost Sense of Taste and Smell) Treatment

Have you ever felt like you could smell something unpleasant even if there was no bad odor around? Or do you have increased sensitivity to odors in comparison to other people? If this is the case, you could be suffering from the neurological disorder dysosmia – a lost sense of smell.

Dysosmia is an olfactory disorder that occurs when your sense of smell is changed. As the olfactory system and oral cavity are connected, dysosmia could affect both sense of smell and taste in some patients. A dysfunction of the olfactory system tends to affect the sense of smell and the ability to detect odors. The condition could affect you through different sub-conditions that include anosmia, parosmia and phantosmia.

The two main dysosmia symptoms are distorted olfactory function and loss of olfactory function. In the case of distorted olfactory function, things that smell pleasant to you normally could smell strange and distorted. Normal odors are relayed to your brain as an unpleasant smell and could resemble burning, chemical, fecal, or rotting smells. In the case of loss of olfactory function, you will not be able to smell anything around you. Sense of taste is hugely dependent on your olfactory senses, so patients who cannot smell tend to lose their ability to taste as well. This sensation of loss of taste is known as ageusia.

Dysosmia can manifest as anosmia, parosmia and phantosmia, so the causes differ based on which condition you are suffering from.

• Patients affected by anosmia tend to have no olfactory response to any odor. The condition could be acute or chronic, and you would react differently to different odors. Anosmia is caused due to a blocked nose or infected nasal polyps or nasal sinuses. Constant use of medication like decongestants and antihistamines can lead to a blocked nose, while some kinds of nasal sprays could damage the olfactory receptor neurons. Structural defects in the nose could also lead to a change in the sense of smell. When the olfactory receptor neurons are damaged completely, it could lead to a complete loss of smell.
• Parosmia is a condition wherein patients tend to distort odors, and it could lead to them not knowing the difference between a pleasant and unpleasant odor. In certain cases, they may not be able to differentiate the taste between drinks and food. The causes of parosmia could include contact with toxics substances or a head trauma that affects the olfactory bulb that is responsible for smell.
• Phantosmia is a condition where patients tend to imagine smells that are not really there. Phantosmia and hallucinations with smell may occur due to neurological disorders including Alzheimer’s and schizophrenia.

The treatment options for dysosmia are limited, though in certain cases, you can be treated so as to restore olfactory senses. How quickly you recover will depend on what kind of olfactory disorder you are suffering from. Treatments could include the application of anesthesia to parts of the nose, systemic medications, and topical medications. In some cases, the olfactory epithelium is excised through an endoscopic transnasal procedure to try and treat phantosmia; this might help restore sense of smell.

The first thing that your doctor will as you for is a detailed case history including questions on whether you have suffered from any head injury or infections of the respiratory system. The diagnostic techniques used predominantly to detect dysosmia are nasal cytology, olfactory nerve testing, sinus transillumination, sniffin’ sticks, and University of Pennsylvania Smell Identification Test (UPSIT).

• Nasal cytology: You will be required to blow your nose into a piece of plastic wrap so that the nasal discharge can be collected. The collected specimen will then be sent to the lab to check your eosinophil levels that are mainly to blame for the start of allergies.
• Olfactory nerve testing: To check if your olfactory nerve is functioning properly, one nostril is blocked while a pungent odor is placed under your nose to test for your reaction. The same process is repeated for the other nostril as well.
• Sinus transillumination: For this test, a bright light is shone over your forehead or cheek while you are in a dark room. A glow will be noticed if the sinus is clear on both the areas of the cheek and the hard palate of your open mouth.
• Sniffin’ sticks: This test is mostly used to diagnose anosmia and parosmia. The odor discrimination test, odor identification test, and odor threshold test are conducted to find out your olfactory senses reaction to various stimuli.
• University of Pennsylvania smell identification test: This test requires that four self-administered booklets be used to trigger your sense of smell, each booklet has ten stimuli within it. You are required to pick up one of the booklets and identify the types of odors present within that particular booklet. This test gives you a quick way to identify the olfactory functions and if you are suffering from an upper respiratory infection or sinusitis.

http://www.ncbi.nlm.nih.gov/pubmed/3541661

http://www.ncbi.nlm.nih.gov/pubmed/11901275

http://www.utmb.edu/otoref/grnds/Olfactory-2003-1126/Olfactory-2003-1126.htm