Antiparasitics

Question 1

What are the 3 groups of drugs used for amebiasis?

Answer 1

• Luminal - act on parasite in bowel lumen
• Systemic - active both in intestinal wall and liver
• Mixed - avtive against both luminal and systemic disease

Question 2

Mixes drugs for amebiasis uses,

Answer 2

Metronidazole, Tinidazole

MOA: taken up by protozoa/anaerobic bacteria converted to toxic metabolite by ferroreduction

Uses: Amebiasis (Entamoeba histolytica), Giardiasis (Giardia lambiia), Trichomoniasis (Trichomonas)

AE: Metronidazole can cause disulfiram-like reaction with ethanol due to inhibiton of aldehyde dehydrogenase

Question 3

Intestinal drugs used for Amebiasis?

Answer 3

• Diloxanide
• Iodoquinol: some Entamoeba have resistance from overexpression of p-glycoprotein
• Paromomycin

Question 4

Systemic drugs used for Amebiasis

Answer 4

• Chloroquine
• Emetine
• Dehydroemetine

Useful for treating liver abscesses or intestinal wall infections

Question 5

How to treat each Amebiasis for each severity?

Answer 5

• Asymptomatic, intestinal
  
  • Diloxanide furoate
• Mild-moderate, intestinal
  
  • Metronidazole + Diloxanide furoate
• Severe intestinal
  
  • Metronidazole or Tindazole + diloxanide furoate
• Hepatic Abscess and other Extraintestinal disease
  
  • Metronidazole or Tinidazole + Diloxanide furoate