There are many, many causes of chronic cough and even a very systematic approach may not reveal the cause. A metallic taste may be secondary to medication but in many instances the cause is never found. Fortunately having a metallic taste is seldom an indicator of serious disease.
The following is the Mayo Clinic statement on metallic tastes:
Metallic taste in mouth: A cause for concern?
A metallic taste in the mouth is a fairly common problem — and usually not serious. Although you don't have actual taste buds that detect metals, the perception of the taste is described as "metallic."
A metallic taste can be due to many factors. But the most common causes of a metallic taste are:
• Medications such as some antibiotics, prenatal vitamins and antidepressants, as well as drugs used to treat high blood pressure, rheumatoid arthritis and kidney stones
• Oral problems, including oral infections such as gingivitis or periodontitis, tooth infections, and poor oral hygiene
Sometimes the cause of a metallic taste can't be determined. In many cases, the problem goes away on its own after several months or longer. Proper oral hygiene can help, including regularly brushing your teeth and brushing and scraping your tongue. Done properly, dental restorations — such as fillings and inlays — are rarely the cause a metallic taste.
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Psoriatic arthritis for 30+ yrs, Mild psoriasis, Enbrel for 5+ yrs- light dose, Son had a fundoplication at 2 mo old, Head of bed raised a couple inches. Mom and Grandmother always fiddling with their stomachs. Tea or hot water to settle it was about all needed, Mom is on Pervacid 2x daily. I am a singer, 5' 10" - 182#, Blood type O, Diet is a lot of fiber and I eat very healthy and well.
Nothing in excess, no alcohol, drugs, smoke.
I am a coffee roaster but I limit myself to 1 cup a day. If I dont drink coffee, it doesnt change.
Lungs excellent. Blew a 650 on the...well, whatever its called.
O2 sat is perfect, BP perfect.