What are the side effects of Cranberry juice?

Its very acidic actually so people who get bloated easily should avoid this.

Drinking cranberry juice in large quantities may cause diarrhea and an upset stomach. Cranberry juice contains a high content of sugar and salicylic acid. People with diabetes and glucose intolerance, as well as those allergic to aspirin, should avoid excessive consumption of the juice. Cranberry can also cause kidney stones or an inflammation of the stomach lining if taken in excess.

So have it in limitation to avoid bloating so easy!