If he has had chemotherapy then this probably has caused the metallic taste. I had it for a long time after mine. Everything tasted different, I completely went off all my favourite foods and I was constantly thing the drains smelled, which I was assured they did not. Took quite a while to get back to normal.
not to worry Caran, but an ongoing metallic taste in his mouth was DH’s first sign of kidney issues. According to his renal team, this is quite a common thing but because there are so many other causes, the kidney possibility can be overlooked.
Caran.......Renal cysts are very common and in the vast majority of cases are benign, requiring no treatment.
Woofgang is correct in that in renal disease, metallic taste in the mouth is a feature, but not in the early stages, as the symptom is due to the build up of ammonia in the latter stages of quite advanced kidney disease (Uraemia)