maybe

might work also

another possibility

another idea

Taste disturbance. In the elderly, drug-induced taste disturbances include a reduced (hypogeusia) or a distorted (dysgeusia) sense of taste, rather than a total absence (ageusia) of taste.[4] The mechanism of action of drug-induced alterations in the sense of taste is not known and may involve different areas including peripheral receptors, chemosensory neuronal pathways, and/or the brain.[4] Disturbances in the sense of taste are usually reversible upon discontinuation of the drug, although resolution may take several months.[5]

or
impaired taste perception

more possibilities

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Note added at 2002-07-31 09:06:05 (GMT)
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e.g.
http://www.healthcentral.com/mhc/top/003050.cfm#Definition:

Taste, impaired
Alternative names:
loss of taste; metallic taste; impairment of taste; decreased taste and smell; dysgeusia

Definition:
Taste impairment ranging from distorted taste to a complete loss of taste.

Considerations:
The tongue can \"taste\" only sweet, salty, sour, and bitter sensations. Much of what is perceived as \"taste\" is actually smell.

Taste abnormalities can be caused by anything that interrupts the transfer of taste stimuli to the brain, or conditions that affect the way the brain interprets taste stimuli.

Common causes:
common cold
nasal infection due to infection (such as salivary gland
infections), polyp, etc.
influenza
viral pharyngitis
mouth dryness
aging (the number of taste buds diminishes with age)
heavy smoking (especially pipe smoking) which causes
mouth dryness
vitamin (vitamin B-12) or mineral (zinc in diet) deficiency
injury to the mouth, nose, or head
gingivitis
drug side effects such as antithyroid drugs, captopril,
griseofulvin, lithium, penicillamine, procarbazine, rifampin,
vinblastine, or vincristine
Bell\'s palsy
Sjogren\'s syndrome
streptococcal pharyngitis (strep throat)

Note: There may be other causes of impaired taste. This list is not all inclusive, and the causes are not presented in order of likelihood. The causes of this symptom can include unlikely diseases and medications. Furthermore, the causes may vary based on age and gender of the affected person, as well as on the specific characteristics of the symptom such as quality, time course, aggravating factors, relieving factors, and associated complaints. Use the Symptom Analysis option to explore the possible explanations for impaired taste, occurring alone or in combination with other problems.