Opioids Movantik - new patient - need help

[researcher6969]

My wife is new to opioids after a recent diagnosis of cervical cancer. She's on the butrans patch and takes roxicodone prn. Total time taking around the clock opioids is maybe 1.5 months. She has unbearable, indescribable pain.
About 2 weeks in she blocked up completely in the bowels and was hospitalized for an obstruction after not having a BM for over 5 days. She tried all sorts of laxatives for another 2 weeks and had to continually use suppositories and enemas just to go to the bathroom. Her pain management doctor prescribed Movantik. It's described in a couple of threads on here but its always spelled differently. What we got is definitely spelled Movantik. She's on 25mgs. I'm fairly familiar with opiates due to a recreational habit, but my wife was opioid naive when she started on her prescribed meds and is not abusing them - I know because I check her bottles because I'm worried she's going to start thinking like I do.
Well, 24-36 hours into using Movantik, she started experiencing what I can only describe as opiate withdrawal (she's never experienced WD so doesn't know what it would feel like), and severe pain in her abdomen. She was sweating and alternating between hot/cold, irritable/anxious, had uncontrolled pain, aches throughout her body, unable to sleep, etc. It seems like WD.

Interestingly, she's NOT experiencing any diarrhea and actually had her first normal bowel movement without the use of a suppository or enema this morning. But she's in so much pain she can't get out of bed, her PRN roxis aren't touching it, and she refuses to believe it could be the Movantik / won't stop taking it because of the hell she went through from the constipation. Am I out of my mind here? Is it even possible to go through WD after only 1.5 months on an opiate? It's also totally possible her cancer progressed and she's just more sick; its very advanced stage 4.

Update: I just re-read the product label and her doctor is using it off-label:

APPROVED USE FOR MOVANTIK​

MOVANTIK is a prescription medicine used to treat constipation that is caused by prescription pain medicines called opioids, in adults with long-lasting (chronic) pain that is not caused by active cancer.

I don't understand why having active cancer would be contraindicated, but now I'm more worried.

 

[Snafu in the Void]

It's basically narcan, except it only acts peripherally. This can still cause withdrawal though, because we have opioid receptors in all of our organs not just the brain.

Withdrawal symptoms is one of the listed side effects:

"You may have symptoms of opioid withdrawal during treatment with MOVANTIK, including sweating, chills, diarrhea, stomach pain, anxiety, irritability, and yawning."


And opioid dependence can begin in as little as 2 weeks, so it's very likely she would have some level of dependence after 6 weeks.

Although I do find it a bit odd it's being prescribed even though cancer is specifically contraindicated... surely there must be another option.