GI GI Pharmacology and Medications 2

Question 1

Which medication is used to treat hepatic encephalopathy by reducing gut bacteria that produce ammonia, without being significantly absorbed systemically?

Accepted Answer

Rifaximin

Answer

Rifaximin is a minimally absorbed antibiotic that reduces ammonia-producing gut bacteria and is preferred for preventing recurrent hepatic encephalopathy.

Question 2

Cholestyramine is a bile acid sequestrant used to treat which type of diarrhea?

Accepted Answer

Bile acid malabsorption diarrhea

Answer

Cholestyramine binds bile acids in the colon, preventing them from stimulating fluid secretion, and is effective for bile acid malabsorption (e.g., post-ileal resection).

Question 3

Which drug class is used as first-line prophylaxis for spontaneous bacterial peritonitis (SBP) recurrence in cirrhotic patients with ascites?

Accepted Answer

Fluoroquinolone antibiotics (e.g., norfloxacin) or trimethoprim-sulfamethoxazole

Answer

Long-term norfloxacin or trimethoprim-sulfamethoxazole is used for secondary SBP prophylaxis in cirrhotic patients after a prior episode.

Question 4

Lubiprostone and linaclotide are used to treat constipation-predominant IBS (IBS-C); what is their shared mechanism?

Accepted Answer

Stimulate intestinal chloride secretion, increasing luminal fluid

Answer

Both lubiprostone (ClC-2 activator) and linaclotide (GC-C agonist) increase intestinal chloride and fluid secretion, softening stool and accelerating transit.

Question 5

Alosetron is a 5-HT3 antagonist approved for IBS with diarrhea (IBS-D) in women; which serious adverse effect restricts its use?

Accepted Answer

Ischemic colitis and severe constipation

Answer

Alosetron carries a black box warning for ischemic colitis and severe constipation, restricting it to women with severe IBS-D who fail other therapies.

Gastrointestinal GI Practice Practice Test

Gastrointestinal GI Practice Practice Test

GI GI Pharmacology and Medications 2