Lastly, Fentanyl is one of the the better medications for those with renal (
kidney) or heptic (liver) impairement. Dilaudid is as well.
Oxycodone (with and without tylenol) and Hydrocodone are both not recommended due to the additional metabolism by the liver into oxymorphone and hydromorphone, respectively. There is still some work on the liver regardless to process opioids but Fentanyl, Dilaudid (hydromorphone), and Opana (oxymorphone) put less strain on the liver.