An amebicide (or amoebicide) is an agent that is destructive to

amoeba An amoeba (; less commonly spelled ameba or amœba; : amoebas (less commonly, amebas) or amoebae (amebae) ), often called an amoeboid, is a type of Cell (biology), cell or unicellular organism with the ability to alter its shape, primarily by ...

, especially parasitic amoeba that cause

amoebiasis Amoebiasis, or amoebic dysentery, is an infection of the intestines caused by a parasitic amoeba '' Entamoeba histolytica''. Amoebiasis can be present with no, mild, or severe symptoms. Symptoms may include lethargy, loss of weight, colon ...

Entamoeba

Metronidazole Metronidazole, sold under the brand name Flagyl and Metrogyl among others, is an antibiotic and antiprotozoal medication. It is used either alone or with other antibiotics to treat pelvic inflammatory disease, endocarditis, and bacterial vagino ...

, or a related drug such as

Tinidazole Tinidazole, sold under the brand name Tindamax among others, is a medication used against protozoan infections. It is widely known throughout Europe and the developing world as a treatment for a variety of anaerobic amoebic and bacterial infecti ...

Secnidazole Secnidazole (trade names Flagentyl, Sindose, Secnil, Solosec) is a nitroimidazole anti-infective used to treat bacterial vaginosis and trichomoniasis. It is taken orally. Structurally it actually methyl-metronidazole. Effectiveness in the tr ...

or Ornidazole, is used to destroy amoebae that have invaded tissue. * Several drugs are available for treating intestinal infections, the most effective of which has been shown to be Paromomycin (also known as Humatin). ''E. histolytica'' infections occur in both the intestine and (in people with symptoms) in tissue of the intestine and/or liver. As a result, both tissue and luminal drugs are needed to treat the infection, one for each location. Metronidazole is usually given first, followed by Paromomycin or Diloxanide. ''E. dispar'' does not require treatment, but many laboratories (even in the developed world) do not have the facilities to distinguish this from ''E. histolytica''.

Tissue amebicides

, or a related drug such as

tinidazole Tinidazole, sold under the brand name Tindamax among others, is a medication used against protozoan infections. It is widely known throughout Europe and the developing world as a treatment for a variety of anaerobic amoebic and bacterial infecti ...

secnidazole Secnidazole (trade names Flagentyl, Sindose, Secnil, Solosec) is a nitroimidazole anti-infective used to treat bacterial vaginosis and trichomoniasis. It is taken orally. Structurally it actually methyl-metronidazole. Effectiveness in the tr ...

or ornidazole, is used to destroy amoebae that have invaded tissue. These are rapidly absorbed into the bloodstream and transported to the site of infection. Because they are rapidly absorbed there is almost none remaining in the intestine. For amebic dysentery a multi-prong approach must be used, starting with one of: *

metronidazole Metronidazole, sold under the brand name Flagyl and Metrogyl among others, is an antibiotic and antiprotozoal medication. It is used either alone or with other antibiotics to treat pelvic inflammatory disease, endocarditis, and bacterial vagino ...

500–750 mg three times a day for 5–10 days *

2g once a day for 3 days is an alternative to metronidazole Doses for children are calculated by body weight and a pharmacist should be consulted for help.

Luminal amebicides

Since most of the amoebae remain in the intestine when tissue invasion occurs, it is important to get rid of those also or the patient will be at risk of developing another case of invasive disease. Several drugs are available for treating intestinal infections, the most effective of which has been shown to be paromomycin (also known as Humatin); iodoquinol (also known as Yodoxin) is used in the US; and diloxanide furoate (also known as Furamide) is used in certain other countries. In addition to the tissue amebicides above, one of the following lumenal amebicides should be prescribed as an adjunctive treatment, either concurrently or sequentially, to destroy '' E. histolytica'' in the colon: * Paromomycin 500 mg three times a day for 10 days * Iodoquinol 650 mg three times a day for 20 days Doses for children are calculated by body weight and a pharmacist should be consulted for help.

Amebic liver abscess

For amebic liver abscess: * Metronidazole 400 mg three times a day for 10 days * Tinidazole 2g once a day for 6 days is an alternative to metronidazole * Diloxanide furoate 500 mg three times a day for 10 days (or one of the other lumenal amebicides above) must always be given afterwards Doses for children are calculated by body weight and a pharmacist should be consulted for help.

Acanthamoeba

Propamidine isethionate has been used in the treatment of

Acanthamoeba ''Acanthamoeba'' is a genus of amoeboid, amoebae that are commonly recovered from soil, fresh water, and other habitat (ecology), habitats. The genus ''Acanthamoeba'' has two stages in its life cycle, the metabolically active trophozoite stage a ...

infection.

Treatment by use of primitive medicines

The

Nicobarese people The Nicobarese people are an Austroasiatic-speaking people of the Nicobar Islands, a chain of islands in the Bay of Bengal north of Sumatra, forming part of the union territory of Andaman and Nicobar Islands, India. The Nicobar Archipelago cons ...

have attested to the medicinal properties found in '' Glochidion calocarpum'', a plant endemic to India, saying that its bark and seed are most effective in curing abdominal disorders associated with

.See p. 412 in:

''Naegleria''

Although ''

Naegleria ''Naegleria'' is a genus consisting of 47 described species of protozoa often found in warm aquatic environments as well as soil habitats worldwide. It has three life cycle forms: the amoeboid stage, the cyst stage, and the flagellated stage, an ...

'' is sometimes considered

amoeboid An amoeba (; less commonly spelled ameba or amœba; : amoebas (less commonly, amebas) or amoebae (amebae) ), often called an amoeboid, is a type of cell or unicellular organism with the ability to alter its shape, primarily by extending and r ...

, unlike Acanthamoeba or Balamuthia it is not closely related to the Amoebozoa (it is much more closely related to ''

Leishmania ''Leishmania'' () is a genus of parasitic protozoans, single-celled eukaryotic organisms of the trypanosomatid group that are responsible for the disease leishmaniasis. The parasites are transmitted by sandflies of the genus '' Phlebotomus'' ...

'') and agents used to treat ''Naegleria'' infections are usually addressed separately.

References

External links

* {{Agents against amoebozoa Amoebozoa