All Entamoeba histolytica infections should be treated.[1]Haque R, Huston CD, Hughes M, et al. Amebiasis. New Engl J Med. 2003;348:1565-73.
http://www.ncbi.nlm.nih.gov/pubmed/12700377?tool=bestpractice.com
[5]Stanley SL Jr. Amoebiasis. Lancet. 2003;361:1025-34.
http://www.ncbi.nlm.nih.gov/pubmed/12660071?tool=bestpractice.com
[7]Shirley DT, Farr L, Watanabe K, et al. A review of the global burden, new diagnostics, and current therapeutics for amebiasis. Open Forum Infect Dis. 2018 Jul;5(7):ofy161.
https://academic.oup.com/ofid/article/5/7/ofy161/5049601
http://www.ncbi.nlm.nih.gov/pubmed/30046644?tool=bestpractice.com
Treatment should be given as soon as the diagnosis is considered, after samples have been taken for testing, as amebiasis is a potentially fatal illness.
Symptomatic patients should initially be given a nitroimidazole (e.g., metronidazole, tinidazole).[7]Shirley DT, Farr L, Watanabe K, et al. A review of the global burden, new diagnostics, and current therapeutics for amebiasis. Open Forum Infect Dis. 2018 Jul;5(7):ofy161.
https://academic.oup.com/ofid/article/5/7/ofy161/5049601
http://www.ncbi.nlm.nih.gov/pubmed/30046644?tool=bestpractice.com
[17]Centers for Disease Control and Prevention. CDC Yellow Book 2026: health information for international travel. Section 5: travel-associated infections & diseases - post-travel diarrhea. Apr 2025 [internet publication].
https://www.cdc.gov/yellow-book/hcp/post-travel-evaluation/post-travel-diarrhea.html
Nitroimidazoles have excellent tissue penetration and are active for both luminal and invasive infection. There is no recognized resistance to this class of drug. This should be followed with a luminal agent (e.g., paromomycin) to eradicate gut colonization and prevent relapse.[1]Haque R, Huston CD, Hughes M, et al. Amebiasis. New Engl J Med. 2003;348:1565-73.
http://www.ncbi.nlm.nih.gov/pubmed/12700377?tool=bestpractice.com
[5]Stanley SL Jr. Amoebiasis. Lancet. 2003;361:1025-34.
http://www.ncbi.nlm.nih.gov/pubmed/12660071?tool=bestpractice.com
[7]Shirley DT, Farr L, Watanabe K, et al. A review of the global burden, new diagnostics, and current therapeutics for amebiasis. Open Forum Infect Dis. 2018 Jul;5(7):ofy161.
https://academic.oup.com/ofid/article/5/7/ofy161/5049601
http://www.ncbi.nlm.nih.gov/pubmed/30046644?tool=bestpractice.com
[17]Centers for Disease Control and Prevention. CDC Yellow Book 2026: health information for international travel. Section 5: travel-associated infections & diseases - post-travel diarrhea. Apr 2025 [internet publication].
https://www.cdc.gov/yellow-book/hcp/post-travel-evaluation/post-travel-diarrhea.html
[33]Drugs for parasitic infections. Medical Letter. 2004;46:e1-12.[34]Gonzales MLM, Dans LF, Sio-Aguilar J. Antiamoebic drugs for treating amoebic colitis. Cochrane Database Syst Rev. 2019 Jan 9;1:CD006085.
http://www.ncbi.nlm.nih.gov/pubmed/30624763?tool=bestpractice.com
Adverse effects of these drugs are generally minor, whereas the infection itself is potentially fatal.
Asymptomatic patients also require treatment because of the risk for developing future invasive disease.[1]Haque R, Huston CD, Hughes M, et al. Amebiasis. New Engl J Med. 2003;348:1565-73.
http://www.ncbi.nlm.nih.gov/pubmed/12700377?tool=bestpractice.com
[5]Stanley SL Jr. Amoebiasis. Lancet. 2003;361:1025-34.
http://www.ncbi.nlm.nih.gov/pubmed/12660071?tool=bestpractice.com
They should be treated with a luminal agent alone.[7]Shirley DT, Farr L, Watanabe K, et al. A review of the global burden, new diagnostics, and current therapeutics for amebiasis. Open Forum Infect Dis. 2018 Jul;5(7):ofy161.
https://academic.oup.com/ofid/article/5/7/ofy161/5049601
http://www.ncbi.nlm.nih.gov/pubmed/30046644?tool=bestpractice.com
[35]Blessmann J, Tannich E. Treatment of asymptomatic intestinal Entamoeba histolytica infection. N Engl J Med. 2002;347:1384.
http://www.ncbi.nlm.nih.gov/pubmed/12397207?tool=bestpractice.com
Amebic liver abscess
Percutaneous aspiration is not commonly required. It may be required for patients who do not respond to nitroimidazole treatment in 5 to 7 days, or with large (>5 cm diameter) or left lobe lesions. In patients with large abscesses, draining the abscess in addition to treating with a nitroimidazole could aid in the early resolution of pain and tenderness.[1]Haque R, Huston CD, Hughes M, et al. Amebiasis. New Engl J Med. 2003;348:1565-73.
http://www.ncbi.nlm.nih.gov/pubmed/12700377?tool=bestpractice.com
[2]Petri WA Jr, Singh U. Diagnosis and management of amebiasis. Clin Infect Dis. 1999;29:1117-25.
http://www.ncbi.nlm.nih.gov/pubmed/10524950?tool=bestpractice.com
[5]Stanley SL Jr. Amoebiasis. Lancet. 2003;361:1025-34.
http://www.ncbi.nlm.nih.gov/pubmed/12660071?tool=bestpractice.com
[36]Chavez-Tapia NC, Hernandez-Calleros J, Tellez-Avila FI, et al. Image-guided percutaneous procedure plus metronidazole versus metronidazole alone for uncomplicated amoebic liver abscess. Cochrane Database Syst Rev. 2009;(1):CD004886.
http://www.ncbi.nlm.nih.gov/pubmed/19160244?tool=bestpractice.com
[37]Bammigatti C, Ramasubramanian NS, Kadhiravan T, et al. Percutaneous needle aspiration in uncomplicated amebic liver abscess: a randomized trial. Trop Doct. 2013;43:19-22.
http://www.ncbi.nlm.nih.gov/pubmed/23550199?tool=bestpractice.com