Fill a deep skillet or heavy-bottomed pot with about ½ inch vegetable oil and heat to 375°F. Use a thermometer to monitor the temperature while frying.
Drain the pickle slices and spread them on paper towels. Pat them very dry so the batter sticks better and the pickles do not splatter as much in the hot oil.
In a shallow bowl, whisk together the flour, garlic salt, Italian seasoning, and pepper. Add the water and whisk until smooth. Place the panko breadcrumbs in a separate shallow dish.
Working in small batches, coat the pickle slices in the batter, letting any excess drip off, then press them into the panko until coated on all sides.
Carefully add a few breaded pickles to the hot oil at a time. Fry for 1 to 2 minutes per side, or until golden brown and crisp. Transfer to a paper towel-lined plate or wire rack to drain. Let the oil return to 375°F before adding the next batch.
Serve warm with ranch, fry sauce, buffalo sauce, ketchup, or your favorite dipping sauce.