Can orange juice replenish potassium lost from excessive diarrhea due to a virus?

Depends on…: What u mean by "excessive diarrhea". If diarrhea was severe enough to cause potassium deficiency, u'd probably also be dehydrated & need more than oj to correct problem. Oj, sports drinks, some vitamin waters may slightly replenish potassium loss but should see doc to check potassium & hydration status if the diarrhea was "excessive".

OJ and potassium: Orange juice (oj) is an excellent source of potassium (k). Drinking just one 8-ounce glass of orange juice every day adds 474 mg of potassium to your diet. If you have diarrhea, you not only lose k you also lose magnesium (m) as well. K levels will not increase if a person has a low m level. If your diarrhea is severe. Perhaps you should get your blood taken to see what your k and m levels are.