hi... thanks for choosing healthcaremagic..
your mother is operated for fistula and she has metallic taste
and heart burn.. she could be having drug induced gastritis
group of drugs will cause metallic taste..
see your physician for prescription for gastritis.. pantoprozole with prokinetics like itapride will help your mother to get rid of these symptoms..
if she has kidney failure.. based on the serum creatinine
levels the dose of the drug to be taken is calculated and prescribed.. few drugs are contraindicated in renal failure
that should be taken care of..
see your physician for the prescription and calculation of the doses of antibiotics...
all the very best..