“How long does dye stay in your system after a CT scan?”

You can look it up online for a better explanation, but I believe the contrast is excreted from your system from your urine within 24-36 hours after the contrast CT scan. You just have to drink a lot of water for a day or so and that should flush right through as long as your kidneys are working adequately. You will not see anything in the toilet as it all comes out clear when you urinate it out. Hope that helps.

Not long at all. The contrast is cleared by the kidneys and should be gone within one day.