IBS Flashcards

Flashcards about Etiology and treatments for IBS

What is the Etiology of IBS (Irritable Bowel Syndrome)?

Unclear etiology. Possibly related to psychological issues, increased somatovisceral sensitivity, and motor dysfunction.

Name three bulk forming laxatives

Psyllium, Polycarbophil, and Methylcellulose Products

What is the Mechanism Of Action of osmotic agents like Polyethylene glycol (PEG)?

Cause water retention in the stool, thereby increasing stool frequency.

What are Potential Adverse Drug Reactions (ADRs) of Polyethylene Glycol (PEG)?

Nausea, vomiting, flatulence, and abdominal cramping.

What is the Mechanism Of Action of Senna and Bisacodyl?

Stimulate the mucosal nerve plexus of the colon and may also increase intestinal fluid secretion.

What are the ADRs of Stimulant Laxatives (Senna and Bisacodyl)?

May cause severe abdominal cramping and electrolyte imbalances

What is the Mechanism Of Action (MOA) of Lubiprostone (Amitiza)?

Is a chloride channel activator that acts locally in the gut to open chloride channels on the GI luminal epithelium, which, in turn, stimulates chloride-rich fluid secretion into the intestinal lumen.

What are the ADRs of Lubiprostone (Amitiza)?

Headache, nausea, and diarrhea.

What are the approved uses for Lubiprostone (Amitiza)?

Chronic idiopathic constipation and opioid-induced constipation

What are the contraindications for the use of Lubiprostone (Amitiza)?

Known or suspected mechanical gastrointestinal obstruction

What is the MOA of Linaclotide (Linzess) and Plecanatide (Trulance)?

Minimally absorbed peptide agonist of the guanylate cyclase-C receptor that stimulates intestinal fluid secretion and transit.

What are the ADRs of Linaclotide (Linzess) and Plecanatide (Trulance)?

Diarrhea, abdominal pain, and flatulence.

What are the Contraindications of Linaclotide (Linzess) and Plecanatide (Trulance)?

Known or suspected mechanical gastrointestinal obstruction and age <2 years.

What is the Black Box warning of Linaclotide (Linzess) and Plecanatide (Trulance)?

Dehydration in kids <2 years (linaclotide) and <6 years (plecanatide).

What are the Rome Criteria for Diagnosing IBS?

Recurrent abdominal pain, on average, at least one day per week in the last three months, associated with two or more of the following criteria: Related to defecation, Associated with a change in stool frequency, Associated with a change in stool form

What is the first line treatment for Constipation Predominant IBS?

Bulking agents such as psyllium

What is the first line treatment for Diarrhea Predominant IBS?

Loperamide

What is the MOA of Tenapanor (Ibsrela)?

Sodium/Hydrogen Exchanger 3 (NHE3) Inhibitor that decreases sodium absorption and increases intestinal fluid secretion, thereby improving bowel function.

What is the MOA of Loperamide (Imodium)?

Acts only peripherally. Antisecretory; inhibits the calcium-binding protein calmodulin, and controls chloride secretion.

What is the MOA of Eluxadoline (Viberzi)?

Is a mixed mu-opioid receptor agonist, delta opioid receptor antagonist, and kappa opioid receptor agonist which acts locally to reduce abdominal pain and diarrhea

What is the drug class of Alosetron (Lotronex)?

Selective serotonin 5-HT3 antagonist

For Alosetron (Lotronex), what should patients report to their physician?

Abdominal pain and tenderness, rectal bleeding or bloody diarrhea.

What is the MOA of antispasmodics?

Have anticholinergic effects and decrease spontaneous activity of intestinal smooth muscle

What is the MOA of Rifaximin?

Rifaximin inhibits bacterial RNA synthesis by binding to bacterial DNA-dependent RNA polymerase

What is the MOA of Bile Acid Sequestrants?

Bind with bile acids to form an insoluble complex that is eliminated in the stool

List some of the uses of peppermint oil.

Antiinflammatory, smooth muscle relaxant

How should Antidepressants (tricyclics) be used in treating abdominal pain in IBS?

Start at low doses with the initial dose adjusted based on tolerance and response. Three to four weeks of therapy should be attempted before increasing the dose.

What are the ADRs for Rifaximin?

Peripheral edema, dizziness, fatigue, nausea, and an increase in alanine aminotransferase (ALT) levels

What are the ADRs of Alosetron (Lotronex)?

Abdominal pain, nausea, diarrhea

What are the ADRs of Bile Acid Sequestrants?

Decreased absorption of fat-soluble vitamins (A, D, E, K)

What are the ADRs of Loperamide (Imodium)?

Dizziness and constipation.

What are the ADRs of Eluxadoline (Viberzi)?

Constipation, Pancreatitis, Sphincter of Oddi spasm

What are the ADRs of Tenapanor (Ibsrela)?

Diarrhea, abdominal distension, flatulence, and dizziness

What are the adverse effects of antispasmodics?

Anticholinergic effects may cause dry mouth, blurred vision, urinary retention, constipation, and dizziness.

What is the boxed warning for Alosetron (Lotronex)?

Serious GI adverse events including ischemic colitis and serious complications of constipation

What distinguishes IBS-C and CIC?

Abdominal Pain

What happens if a patient is on medication for IBS-C, but they then cycle to IBS-D?

They would need to add onto their constipation medications, and vice versa.

What is IBS-C?

Constipation Predominant IBS; Patient experiences frequent constipation along with abdominal pain and discomfort.

What is IBS-D?

Diarrhea Predominant IBS; patients experience frequent loose or watery stools along with abdominal discomfort.

What is IBS with mixed bowel movements mean?

IBS where patients experience alternating symptoms of both diarrhea and constipation, along with abdominal pain.

What is unclassified IBS?

A subtype of IBS where symptoms do not clearly fit into the categories of IBS-C, IBS-D, or IBS-M. Patients often experience a combination of symptoms that cannot be distinctly classified.

How to treat a patient with IBS and signs of bloating?

A short trial of rifaximin may be helpful.

What is the treatment pathway for constipation predominant IBS?

1. Start with a bulking agent such as psyllium first (1tbsp of psyllium with one meal daily and titrate to include fiber with2-3 meals/day).

2. Dose should be titrated to bulkier and more easily passed stools.

3. In patients who have failed a trial of soluble fiber, start PEG

4. Patients with persistent constipation despite treatment with PEG, try lubiprostone, linaclotide,tenapanor, or plecanatide.

What is the treatment pathway for diarrhea predominant IBS?

1. First line is loperamide, but if that doesn’t work, then start on bile salt sequestrant.

2. In patients with continued symptoms despite these therapy,eluxadoline is next in line.

3. Severe IBS-D in women may be relieved by alosetron.