Brief Answer:
Send a complete list of blood work

Detailed Answer:
Good evening and I'm sorry your friend has been living with this rather uncomfortable problem of a metallic taste in the mouth. You say that he's had a number of blood tests.

However, there are literally hundreds that could potentially be done. If he can get you a copy of what was done and the results then, perhaps you could upload them to this site in .pdf format and that way I could complement those tests with any other reasonable ones I feel might fit his situation. In someone who is 65 years the first thing I would check before almost anything else would be the medication list which is one of the MOST COMMON reasons why people have metallic tastes. Certain antibiotics and antihistamines are the 2 most common associated with such tastes. People on cancer chemotherapy often complain of metallic tastes as well.

This taste generally goes away once the medications or treatments are stopped. Of course, it almost goes without saying that anybody with unusual or funny tastes in the mouth (metallic or not) should be seen by their dentist for at least a routine checkup to be sure that there are no dental or gingival reasons for the problem. Sinus infections can also alter taste sensations toward the metallic side.

Traumatic brain injury is a more common cause of this type of disorder than people think. Did he have a knock to the head over the past several months of any significance? I know he had a significant blow to the head 6 years but unless he can track this disorder back to several months after the head injury then, that incident has nothing to do with what's going on the past few weeks.

Has he had an MRI of the brain looking for any potential mass lesions in the olfactory groove region such as a meningioma which is one of the most common intracranial reasons for alterations in taste which is often described as a metallic taste?

The steel plate in the head has nothing to do with his symptoms. I would not counsel him to get that removed just for THIS REASON. Also, radiation therapy to the head and neck can cause taste alterations of a metallic nature.

If I've adequately addressed your concerns could you do me a huge favor by CLOSING THE QUERY and be sure to include some fine words of feedback along with a 5 STAR rating to our encounter if you feel my suggestions have helped? Again, many thanks for posing your question.

Do not forget to contact me in the future at: www.bit.ly/drdariushsaghafi for additional questions, comments, or concerns having to do with this topic or others.

This query has utilized a total of 22 minutes of professional time in research, review, and synthesis for the purpose of formulating a return statement.

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