Once you stop taking the opiates, the worst physical W/D symptoms will last
about 5 days. Of course this may vary depeding how long
you were taking the opiates.
Stay hydrated. Drink some gatorade if you can. If you simply can't keep anything down, try sucking on some ice chips. Opiate W/D won't kill you, BUT, if you are dehydrated for to long, you can get sick. So the most important thing is fluids.
Keep posting!! It will get better.