A 55-year-old man with bloody diarrhea and a liver abscess has stool microscopy showing trophozoites of Entamoeba histolytica with ingested RBCs. Metronidazole is started. Which statement about antiamebic therapy is correct?

• A Metronidazole acts as both tissue and luminal amebicide
• B Chloroquine is the drug of choice for intestinal amebiasis
• C Metronidazole is ineffective against E. histolytica and diloxanide furoate is preferred
• D A luminal agent such as paromomycin must follow metronidazole to eradicate cysts ✓

Explanation

Metronidazole is a tissue amebicide but has poor activity against luminal cysts. A luminal agent such as paromomycin or diloxanide furoate must follow to prevent relapse and carrier state. Option A is incorrect because metronidazole does not reliably clear luminal infection. Options C and B are factually wrong regarding amebiasis treatment.

Reference: Katzung Basic and Clinical Pharmacology, 15th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.