That would actually be a step down. She has been on morphine ER for 8-10 years. It doesn't lose it's effectiveness.
Prior to that, she had fentanyl patches. They worked, but patches suck. When she switched doctors (her previous doctor moved) the new doctor switched her off of the patches because the oral meds give you better control. Patches don't deliver medication in a uniform manner. There is a ramp up and a ramp down. In theory, a patch lasts three days, but in practice it is not as effective at the start and end. So she would have to overlap the patches putting a new one on after two days and removing the old after the third. If you lose track, a new patch takes longer to take effect. With the oral, it's much easier to manage.
Also, for chronic pain, things like vicodin and norco, in my opinion, suck. Plus they are bad for your liver because of the tylenol in them. People usually are given these with instructions of "as needed." This makes them much easier to abuse (I need more) or run out early. Time release pills are much better. The idea, according to her doctor, is to keep a constant level of medication in her system. You don't want peaks and valleys, but a constant level.
In all this time, she has not had a problem with medications losing effectiveness. There are a number of other things she takes, but just the one item for pain. It's really not that bad. When she misses a dose, she can still function. if she misses a second, she'll notice because she'll feel a little under the weather. She regularly takes Mirolax for the constipation. She's also on Ritalin for ADHD, which helps with her energy level. (For those that don't know, Ritalin is not a depressant that dopes people up. It's speed.) Unless they are told, know one knows my wife has any problems. It doesn't affect her work and I doubt anyone there even know she's sick.