Try Avoiding Oranges, Grapefruit, Pineapple to Reduce Irritation
Citrus is thought to irritate the bladder (even though, in general, it's wise to eat plenty of fruits and vegetables for their healthy, vitamin-rich liquid and fiber). Beware especially of oranges, grapefruits, lemons, limes, and tangerines. Pineapple, not technically a citrus fruit (even though it often appears in the same tropical salads), is also a culprit because it's highly acidic.
Also avoid citrus in juice form (orange juice, grapefruit juice, lemon juice).
Better: Try substituting nonacidic whole fruits, such as bananas, apples, pears, and berries.