Loss of taste; Metallic taste; Dysgeusia
Taste impairment means there is a problem with your sense of taste. Problems range from distorted taste to a complete loss of the sense of taste. A complete inability to taste is rare.
The tongue can detect sweet, salty, sour, savory and bitter tastes. Much of what is perceived as "taste" is actually smell. People who have taste problems often have a smell disorder that can make it hard to identify a food's flavor. (Flavor is a combination of taste and smell.)
Taste problems can be caused by anything that interrupts the transfer of taste sensations to the brain. It can also be caused by conditions that affect the way the brain interprets these sensations.
The sensation of taste often decreases after age 60. Most often, salty and sweet tastes are lost first. Bitter and sour tastes last slightly longer.
Causes of impaired taste include:
Other causes are:
- Ear surgery or injury
- Heavy smoking (especially pipe or cigar smoking)
- Injury to the mouth, nose, or head
- Mouth dryness
- Medicines, such as thyroid drugs, captopril, griseofulvin, lithium, penicillamine, procarbazine, rifampin, clarithromycin, and some drugs used to treat cancer
- Swollen or inflamed gums (gingivitis)
- Vitamin B12 or zinc deficiency
Follow your health care provider's instructions. This may include changes to your diet. For taste problems due to the common cold or flu, normal taste should return when the illness passes. If you smoke, stop smoking.
When to Contact a Medical Professional
Call your provider if your taste problems do not go away, or if abnormal tastes occur with other symptoms.
What to Expect at Your Office Visit
The provider will perform a physical exam and ask questions, including:
- Do all foods and drinks taste the same?
- Do you smoke?
- Does this change in taste affect the ability to eat normally?
- Have you noticed any problems with your sense of smell?
- Have you recently changed toothpaste or mouthwash?
- How long has the taste problem lasted?
- Have you been sick or injured recently?
- What medicines do you take?
- What other symptoms do you have? (For example, appetite loss or breathing problems?)
- When is the last time you went to the dentist?
If the taste problem is due to allergies or sinusitis, you may get medicine to relieve a stuffy nose. If a medicine you are taking is to blame, your may need to change your dose or switch to a different drug.
A CT scan or MRI scan may be done to look at the sinuses or the part of the brain that controls the sense of smell.
Baloh RW, Jen JC. Smell and taste. In: Goldman L, Schafer AI, eds. Goldman-Cecil Medicine. 25th ed. Philadelphia, PA: Elsevier Saunders; 2016:chap 427.
Doty RL, Bromley SM. Disturbances of smell and taste. In: Daroff RB, Jankovic J, Mazziotta JC, Pomeroy SL, eds. Bradley's Neurology in Clinical Practice. 7th ed. Philadelphia, PA: Elsevier Saunders; 2016:chap 19.
Travers JB, Travers SP, Christian JM. Physiology of the oral cavity. In: Flint PW, Haughey BH, Lund V, et al, eds. Cummings Otolaryngology: Head & Neck Surgery. 6th ed. Philadelphia, PA: Elsevier Saunders; 2015:chap 88.