Level pain relief. Good prolonged and level amount of pain relief for chronic conditions that have pain. Like any narcotic, addiction is possible. Building up a tolerance to narcotics also inherent to chronic narcotic exposure.
Duragesic (fentanyl) patch. Upsides- for chronic pain and gives you steady state levels that are not seen with short acting opiods. Downsides- very potent. Not helpful for acute pain. Often needs a rescue pain med as well.