I can see from your question that stomach acid has been considered and treated.
I disagree that h pylori causes metallic taste.
In fact, a persistent metallic taste must be viewed from a much wider perspective, as it can mean any of thje following.
· Dry mouth, mouth breathing
· Common cold
· uppper respiratory infection
· Salivary gland infection
· Sore throat
· Strep throat
· Viral infection
· Burning; biting the tongue
· Chemical poisoning
· Head, nose,or mouth injury
· Bell’s palsy
· Dental or orthodontic appliances
· Dental problems
· Inflammation of the tongue
· Hay fever
· Nasal polyps
· Neurological disorders
· brain damage
· Radiation therapy to the head or neck
· Sjogren’s syndrome; autoimmune disorder
· Surgery to the ears, nose or throat
· Vitamin B12 deficiency
· Zinc deficiency
· Acetylcholine esterase inhibitors for Alzheimer’s disease
· Antithyroid drugs
Please take this list and go over it with your doctor.
There is no real reason to get an endoscopy unless they are going to do PH monitoring. This will show if you still have acid despite treatment. Doing and endoscopy alone will not be very useful.
I am a double board certified US doctor.
Please click a positive rating on my post if you want me to receive credit for my expertise.
Please let me know if you have further questions.