my dad is diagnosed with FSGS (Focal Segmental Glomerulosclerosis) and while he is currently on dialysis and on the waiting list for the kidney transplant, we’re trying to cope with this condition the best we can. He is, of course, on renal diet, meaning he has very limited fluid intake and we’re trying to figure out what would be the best drink, besides water, to include in his daily liquid intake. He cannot drink orange juice in any form, but I’m not sure how much sense there is in recommendations like coconut juice, carrot juice or even fruit tree or liqui fruit. And one more thing - he is completely avoiding drinking alcohol, but would an occasional glass of cola do him too much harm?
one important thing you need to keep in mind that all protein-containing drinks will increase the protein levels in urine, and that is something FSGS patients need to avoid. Cola contains both caffeine and carbohydrates, with caffeine being more of a problem since it leads to further dehydration, so your husband will just end up thirstier and with bigger urge to urinate.
My recommendation is to stick to the tea, ice or hot - you can get them in fruit flavors or try sticking to simple ones like green tea or whichever one your husband prefers. Only thing to keep in mind is that some teas also contain potentially dehydrating substances, so try keeping the tea intake in order with your husband's renal diet,
Wish you all the best,