When BUN and creatinine rise; there is electrolyte imbalance especially of potassium. This is further compounded by the vomiting, which may cause potassium losses in the stomach juice. Both of these factors combined; paralysis of the intestines or decreased movements of the intestines may occur. Once the BUN creatinine gets better; the potassium too gets better, and so the bloating would decrease significantly. Thus he should be able to take orally without much problem. He need to avoid proteins in the diet. That does not let the creatinine rise. And thus the cycle of the problem would not initiate.
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No. He can't take Palak or leafy vegetable or fruits which contain high potassium as there would be retention of potassium in the kidney failure. He needs to take food with less potassium and less protein (which is uremic diet prescribed in kidney failure). That time, due to likely potassium loss from the stomach juice might have decreased potassium and bowel paralysis. I just wrote that to explain the phenomenon. Now with BUN creatinine getting decreased, the things would be far better and he would be able to take orally as there would be no nausea, vomiting and bloating.
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