Hilary Ugras, NP, on IBS-C Medical Therapies

Nurse practitioner Hilary Ugras reviews the types of medical therapies available for treating IBS-C and how to position them in treating patients. 

Hilary Ugras, MSN, FNP-BC, is a nurse practitioner with a focus in GI motility disorders working at the Beth Israel Deaconess Medical Center in Boston, MA.

CLINICAL PRACTICE SUMMARY

IBS-C Medication Management

• Irritable bowel syndrome with constipation (IBS-C) presents with constipation and abdominal pain/bloating, and AGA guidelines recommend selecting therapy based on the dominant symptom(s), with dose titration and combination therapy as needed in outpatient practice.
• Constipation-targeted therapies include polyethylene glycol (PEG) OTC laxative (powder; 1 capful once daily up to twice daily, patient-titrated) for constipation only; linaclotide (secretagogue; 3 dose options) with a strong guideline recommendation for treating both constipation and pain; plecanatide (secretagogue; 3 mg once daily, single dose); lubiprostone (secretagogue; 8 mcg twice daily for females ≥18 years with IBS-C; 24 mcg twice daily approved for chronic idiopathic constipation); and tenapanor (sodium inhibitor; 50 mg twice daily, single dose) for constipation and pain, including in patients who fail to respond to secretagogues.
• Pain-targeted adjuncts after constipation is treated include low-dose tricyclic antidepressants (off-label; e.g., nortriptyline, noting constipation risk), antispasmodics (dicyclomine or hyoscyamine, as needed; weaker evidence), and encapsulated peppermint oil for pain/cramping; SSRIs lack sufficient guideline evidence for neuromodulation in IBS-C.

TRANSCRIPT

Hello, my name's Hillary Ugras. I'm a nurse practitioner in Boston, Massachusetts at Beth Israel Lahey Health, and I'm here today to talk to you about IBS-C and specifically medication management.

So as we know, IBS-C has two main symptoms that we think about, one being constipation, the other being that abdominal discomfort or bloating. So when I think about medication therapy, I think about what symptom are we targeting, and that's really then how best we can treat our patients. So specifically, the guidelines we have are from the AGA about medications and how to select and what to select.

First, I think we think about medications that will treat constipation. So we have the secretagogues. We think about PEG or polyethylene glycol, which is an over-the-counter laxative, which will help draw water into the colon. This is a nice option for treating constipation because the patient can dose titrate it. It comes in a powder form. You can start with one cap full of powder once a day and go up to one cap full of powder twice a day. If it's too strong, the patients can titrate it on their own and vice versa. So this is going to primarily treat constipation.

Moving on then to the prescription options, we have linaclotide, also a secretagogue. It's increasing the intestinal fluid secretion, and it also has an effect on reducing pain. So very helpful if patients are having both pain and constipation. This comes in 3 doses, so also helpful that you can maybe start at a moderate dose, which is what I do with my patients. And if it's too strong, you reduce the dose. If it's not enough, then you increase the dose. The level of evidence is a strong recommendation for the guidelines.

Next, we have other medications that in the guidelines they're conditionally recommended. Other secretagogues we have, we have plecanatide. There's only one dose in this, and so it may be helpful if it works for the patient, but again, you can't down-titrate it or up-titrate it. And the dose is 3 milligrams once a day. Then we have lubiprostone. This is approved for patients that are 18 years of age or older that are female with IBS-C at a dose of 8 micrograms twice a day. It is approved at a higher dose of 24 micrograms twice a day for chronic idiopathic constipation. And so you may be using your lower dose in the patients with IBS-C or higher dose in chronic idiopathic constipation, and you may be able to dose titrate for both.

Then we have tenapanor, which is not a secretagogue. It is a sodium inhibitor. It increases stool water, and it also may reduce visceral hypersensitivity in patients. So it comes in at one dose, it's 50 milligrams, and it's taken twice a day. Again, just one dose, but may be helpful in patients maybe that have failed the secretagogues, and again, treats both constipation and pain.

Then if we've treated our constipation sufficiently with one of these agents, we think about how can we then target pain as an adjunctive therapy. So we have the TCAs or the tricyclic antidepressants, and these are used at a much lower dose than we would be treating, say, someone with depression. We're using them off label, again, when abdominal pain is still a symptom that we need to target. The TCAs are classically, the main hallmark side effect is constipation because of their anticholinergic effect. So note that when you're giving them, you need to make sure that you're then adequately treating the patient's constipation or using a low dose. Nortriptyline is one of the more frequent TCAs that are used for treating abdominal pain in our IBS-C patients.

Other options are antispasmotics. They may help with cramping. The evidence is weaker. Options for these are dicyclomine or hyoscyamine, and you can use them on demand or as needed for patients for pain. Also, encapsulated peppermint oil, there's some evidence that this may be helpful for treating pain and cramping. The SSRIs are sometimes referenced or used, but there's not really enough evidence in the guidelines to suggest their use as a neuromodulator for our IBS-C patients.

So overall, in summary, when we treat IBS-C, we're really looking at the symptoms and individualizing our treatment approach for our patients. Do they have primarily constipation, abdominal pain, bloating, or both? And you're selecting an agent that treats all of their symptoms. You may need dose titration, you may need to switch agents, and you may need a combination depending on your patient. Thank you so much.