I have been on pain killers (hydro) for awhile for chronic pain. While really sick with flu SWIM stopped taking them for several days, went through some Withdrawals and then after it was all over felt fine. I know the more pain killers you take the less your body relies on itself to kill the pain. After being off them for awhile I had A LOT less pain. Going days without any even OTC pain pills. I had alittle pain and gave in and took a dose. After doing so the pain actually increased?! It was directly from the hydros. Why?