What kind of "carbs" can you NOT eat? If you mean things like pasta, sugar, cereal and bread..that's just crap period.
Just eat a lot of fruit and vegetables for a few days, it's not that hard. Blend a bunch of fruits and drink them. Or eat good carbs like oatmeal. Apples and apple juice are great for flushing anyway because the malic acid in it can help soften stones.