Medical Pharmacology Chapter 27: Gastrointestinal Pharmacology Practice Questions

Rifaximin (Xifaxan
1. FDA-approved for diarrhea-predominant IBS.
2. Rifaximin is classified as a bacterial RNA synthesis inhibitor.
3. Both
4. Neither
Rifaximin absorption and biotransformation:
1. Well absorbed
2. Metabolized by the cytochrome P450 drug metabolizing system (isoform: CYP3A)
3. Both
4. Neither
Rifaximin adverse reaction(s):
1. Nausea
2. Dizziness
3. Fatigue
4. A & B
5. B & C
6. A & C
7. A, B & C
Additional rifaximin adverse effect(s):
1. Peripheral edema
2. Ascites
3. Increased serum alanine aminotransferase.
4. A & B
5. B & C
6. A & C
7. A, B & C
Should diarrhea get worse following rifaximin therapy, C. difficile enterocolitis, causing a severe infectious diarrhea should be considered:
1. True
2. False
Anticholinergics may be used in patients with irritable bowel syndrome.
1. True
2. False
Among the anticholinergic drugs, most common drugs are classified as nonspecific muscarinic receptor blockers. Example(s) of such drugs include(s):
1. Dyclonine
2. Hyocyamine
3. Both
4. Neither
Quaternary drug(s), anticholinergic agents, may be advantageous in treating IBS
1. Glycopyrrolate
2. Methscopolamine (off-label use)
3. Both
4. Neither
In the anti-cholinergic category, glycopyrrolate is rarely used in this setting, although available as an oral solution and as an injectable.
1. True
2. False
Anticholinergic agents in the context of irritable bowel syndrome:
1. May be used on an as-needed basis
2. May be used before meals to reduce pain and fecal urgency that may occur.
3. Both
4. Neither

Medical Pharmacology: Gastrointestinal Pharmacology Practice Questions