While there isn't much you can do to correct this, it's during this period that a lot of electrolytes are removed from the body. I strongly recommend that you take supplements with an electrolyte drink for the first week or two of starting a ketogenic diet. The hard truth is that the available electrolyte products are high in sugar and unfortunately lack real electrolytes. LMNT Recharge is a delicious electrolyte blend that replaces vital electrolytes without the sugars or questionable ingredients found in traditional sports drinks.
Instead of drinking a glass of water, drink an oral rehydration solution like DripDrop ORS, which also contains electrolytes that are essential for hydration.