What do you need to know about the underlying cause?
Loss of smell can be partial (hyposmia) or complete (anosmia), and may be temporary or permanent, depending on the cause.
Even a partial loss of smell could cause you to lose interest in eating, which in extreme cases, might lead to weight loss, poor nutrition or even depression. Some people add more salt to bland foods, which can be a problem if you have high blood pressure or kidney disease. Your sense of smell is also crucial for warning you of potential dangers such as smoke or spoiled food.
A stuffy nose from a cold is a common cause for a partial, temporary loss of smell. A blockage in the nasal passages caused by a polyp or a nasal fracture also is a common cause. Normal aging can cause a loss of smell too, particularly after age 60.
Conditions that cause temporary irritation or congestion inside your nose may include:
- Acute sinusitis (nasal and sinus infection)
- Allergic rhinitis
- Smoking
- Nasal polyps
- Alzheimer's disease
- Brain surgery
- Brain tumor
- Diabetes
- Huntington's disease
- Multiple sclerosis
- Medications
- Parkinson's disease
- Radiation therapy
- Xerodermatosis
- Schizophrenia
- Traumatic brain injury
- Zinc deficiency
When to see a doctor
Loss of smell caused by colds, allergies or sinus infections usually clears up on its own after a few days. If this doesn't happen, consult your doctor so that he or she can rule out more-serious conditions.
Additionally, loss of smell can sometimes be treated, depending on the cause. Your doctor may give you an antibiotic to treat a bacterial infection, or remove anything blocking your nasal passage. But in some cases, loss of smell can be permanent.
Source:
https://www.mayoclinic.org/symptoms/loss-of-smell/basics/definition/sym-20050804
