A comprehensive review of opioid-induced constipation diagnosis strategies and foundational treatment guidelines.
Theresa Mallick-Searle, MS, NP-BC, ANP-BC: How many times in the emergency department do you ask, when a patient comes in for new abdominal pain, “When was your last bowel movement?”
Stephen Anderson, MD, FACEP: That question isn’t necessarily the direct question. It tends to be more often, “Do you have problems with constipation or diarrhea?” And we’ll talk a little about some of the criteria that we look for with this, but that should be part of any conversation. Most diagnoses are made first by history, second by physical exam, and third by tests.
David Wang, MD: Perfect. I think we definitely have the case of this is an important issue.
Brett B. Snodgrass, FNP-C, CPE, FACPP, FAANP: I’d add 1 thing though, David. One thing to think about too, as prescribers, especially in outpatient settings when we’re thinking about prescribing an opioid, is that it’s also not the first adverse effect we’re going to think about. I’ve got to think if the patient is going to be safe taking the opioid. I’ve got to think about the family that might have access to it. I’ve got to think about all those things. Constipation oftentimes is low on the list, and therefore, it might be a second or a third visit before we ever get to the constipation question.
David Wang, MD: Certainly, it’s a less visible symptom or adverse effect of a well-attended medication class. Steve, you alluded to how to diagnose and then started on how to treat opioid-induced constipation. Jeff, I might ask you, could you tell us about how you actually make this diagnosis? What are the things we should keep in mind?
Jeffrey Fudin, BS, PharmD, DAIPM, FCCP, FASHP, FFSMB: That’s a great question, and I’m going to actually call on my pharmacy colleagues out there to try to be more astute with the questions that we ask these patients, because a lot of times, the patients end up in a pharmacy first. There is something called the Rome IV criteria for functional gastrointestinal disorders, and that looks like at a number of domains. For example, if the patient has had fewer than 3 spontaneous bowel movements a week, that’s important. If they’re straining—actually, then there are a bunch of criteria for if the patient is experiencing them 25% or more of the time. That would be straining, lumpy stools, a sensation of blockage, incomplete evacuation, or if the patient feels they have to do a manual manipulation. If any of those happen 25% or more of the time, that would meet the Rome IV criteria. And they are simple questions to ask.
Richard Rauck, MD: I think there are 2 components you alluded to there, Jeff. They are what I think of as the quantitative and then the qualitative parts, right? It’s been a topic, particularly when these drugs were being studied, as to how best look at their efficacy and obviously against placebo. The FDA, as you know, came down on the quantitative side, because they’re wanting a primary end point to be a number of subcutaneous bowel movements, as you referenced. I think a lot of us as clinicians think the qualitative components are equally, and sometimes more, important: that issue straining, as you alluded to, or just difficulty having a bowel movement or hard lumpy stools with incomplete evacuation. I think we clinicians need to be astute to both of those categories and not just focus on 1 or the other.
Stephen Anderson, MD, FACEP: I really have to stress, in the emergency department, opioid-induced constipation is not necessarily a diagnosis of exclusion, but there are a number of steps you have to go through first before you latch on to that diagnosis. The most common presentation is not constipation; it’s abdominal pain or rectal pain. And really, it starts with your history. Part of that might be the prescription drug monitoring program [PDMP], which would give you an idea this person might be at risk, and I really need to stress that a PDMP is a conversation starter, not a conversation stopper. It’s not, “We’re done talking here.” It’s, “Let’s go down this road and explore what we can do to help.”
But the next thing is physical exam, and I can’t stress enough that a lot of the information I get is made within three inches of a physical exam. It involves a rectal exam on patients, which is important. And finally, I would say that the work-up might entail laboratory exams, it might entail CT [computed tomography] scans, etc, before you get to that final diagnosis. You may have an inkling that this is where you’re headed. But I wouldn’t latch onto it just because it’s abdominal pain. I haven’t had a bowel movement for a couple of days, and I’m on an opioid.
David Wang, MD: Certainly, in my palliative practice I see a lot of patients with malignancy, with just terrible pain, who are on chronic opioids. Theresa, I imagine this is a population that you see as well. Can you talk about the NCCN [National Comprehensive Cancer Network] Guidelines for that?
Theresa Mallick-Searle, MS, NP-BC, ANP-BC: Absolutely. This is a patient population that I see quite frequently, both in the outpatient as well as in the hospital setting. The National Comprensive Cancer Network, or NCCN, established a set of guidelines to help clinicians direct treatment when it comes to constipation, specifically opioid-induced constipation. It starts, like many other guidelines, with looking at behavioral-management strategies: diet, exercise, and stress reduction as the first and foremost groundwork in terms of managing constipation, opioid related or not.
Then it goes into looking at over-the-counter laxatives. Recommendations for stool softeners and over-the-counter laxatives is first line in terms of pharmacotherapy. Then it looks at second line, more of the osmotic- or the saline-type laxatives, and then quickly goes on to the PAMORAs [peripherally acting mu opioid receptor antagonists] as a treatment option when the above fail.