Can zinc be given in a diabetic patient

A 72 yr old male has been suffering from such lesions on all the limbs associated with severe itching. He has been suffering since last 2 years. Kindly diagnose and suggest the management.

65 y M c/o itching and burningsensations 6months this type of skin in hands rt gr toe when cracking of skin occurs its painful and burning

75 yr...old pt.having this type of complication c/of no itching...inside burning ...also on buttocks area....suffering from last 15 days....

what is this comdition? complains of burning sometimes oozing since last one year

sodium citrate is generally used in metabolic acidosis or as an emulsifiers but why there is always sodium citrate in anti-cold syrups.. plz let me know?