Smell is a sense that causes an automatic emotional response and physical reaction. It may draw you in toward pleasure or repel you away from danger. Smell can improve your sense of well being or stimulate a desire to throw up. So should this sensation fail to work properly, your quality of life is impacted both in mood and exposure to physical harm.
You react to a smell because substances in the environment release chemicals into the air, what’s referred to as their scent or aroma. These chemicals are drawn in when you breath or given off by food as you chew. As the chemicals pass over olfactory sensory neurons in the nose, these receptor neurons send signals to your brain for identification.
Olfactory receptor signals are sent to your brain’s cortex via the limbic system. The limbic system is the area of your brain believed to trigger emotional responses. That explains an emotionally charged reaction to something in the air or food.
A smell disorder means you’ve lost your ability to sense a smell or the way you perceive a smell has changed. Another problem related to smell is your food tastes different. Therefore, what was once a pleasure to smell or eat may become repulsive when suffering from this health condition.
There are numerous causes for a loss of smell, including:
- head injury
- nasal polyps
- lead poisoning
- dental problems
- deviated septum
- hormonal changes
- radiation treatment ~ head, neck cancer
- rhinitis, allergic rhinitis ~ hay fever, allergy
- chemical exposure ~ insecticides, solvents
- upper respiratory infection ~ influenza, cold
- drugs ~ antibiotics, antihistamines, decongestants
- nervous system disorder ~ Parkinson’s, Alzheimer’s, multiple sclerosis
Sometimes the cause for a loss of smell cannot be found.
Smell disorders are treated by an otolaryngologist. Treatment for smell problems may be as simple as reducing nasal congestion caused by colds, allergies and sinus conditions with OTC decongestants or antihistamines. Or lifestyle changes that have you avoid allergens or quit smoking. Or surgical removal of polyps or a benign tumor may restore your sense of smell.
In some cases (e.g. aging) a smell disorder is a permanent problem and must be treated by replacing its signal. For example, while cooking you can no longer rely on smell to notify you that your food is done. So to prevent your food from being burnt some type of sound device (e.g. cooking timer) can provoke you to check on it instead.