Medications that are chewed, rather than swallowed, may cause a temporary metallic
taste at the back of the tongue. Other medications, such as Flagyl, tetracycline, penicillamine,
Biaxin, ethambutol, biguanides, or allopurinol, can cause a metallic taste because they get into the mouth through salivary secretions or directly from the blood.
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Pregnancy hormones can do strange things to all parts of your body – even your taste buds.