Brief Answer:
Long list of causes; in your case-medications

Detailed Answer:
Hello ma'am and welcome.

Thank you for writing to us.

I have gone through your query and information with diligence and would be more than happy to help you with that information ma'am.

I should rightfully start by saying that there are numerous causes for a metallic taste in the mouth which is why we usually examine the patient for other symptoms as well. As I cannot physically examine you, I shall list all the possible causes that can cause a metallic taste in the mouth. Please forgive me if the list is long, I only wish to provide you with all the information so you may discuss the same with your doctor. They are:

-Medications: As you are on several medications, this could be the most likely cause in your specific case, but it is still best to run this through your treating doctor
-Allergies
-Metal overload
-Excess marine food consumption
-Exposure to inhaled environmental chemicals
-Infections in the oral cavity
-Inflammation in the oral cavity
-Sinus infections
-Hormonal fluctuations
-Nervous system abnormalities (eg. brain, blood vessels, etc.)
-Autoimmune diseases
-Sjogren's syndrome
-Diabetes
-Hyperparathyroidism
-Renal abnormalities
-Nutritional deficiencies
-Systemic diseases

I can understand how this list might be really long and difficult to relate to, which is why you should leave it to your doctor to accurately find the cause. In my opinion, if you do not have any new symptoms other than those brought about by arthritis, RLS and varicose veins, then the cause is most probably the long list of medications you are on.

I hope you find my response both helpful and informative ma'am. Please feel free to write back to me for any further clarifications, I would be more than happy to help you.

Best wishes.

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