"i have taken levorphanol for 18-months.  this is the absolute best pain medication i have ever taken. i have fibromyalgia, rheumatoid arthritis and severe lumbar-sacral issues that are too far gone for surgery to help.  this pain medicine has a half-life of 8  hours.  100% of pain is gone... it even relieves nerve pain.  all the pain relief without the foggy &#039;codone-head&#039; that you get when you take any of the &quot;codones&quot;.  it is relatively inexpensive also.  i totally 100% recommend this pain medicine for anyone with moderate to severe chronic pain."