Albendazole (Zentel) listing extended to treat hookworm and strongyloidiasis
Published in NPS RADAR
Date published: About this date
Life cycle | Symptoms | Diagnosis and treatment | Safety | Federal government assistance for refugee health assessments | References
The streamlined authority listing for albendazole tablets (200 mg) has been extended as of 1 March 2010 to include treatment of strongyloidiasis and hookworm.1
Strongyloidiasis and hookworm are endemic in tropical and subtropical regions, including Africa, Asia and the Americas. They are also common in Aboriginal and Torres Strait Islander communities in northern Australia.2–4
Albendazole is the treatment of choice for hookworm.3,5 In strongyloidiasis, ivermectin (Stromectol) is the treatment of choice but albendazole is an alternative for those in whom ivermectin is unsuitable (see below).3,5
Both hookworms and Strongyloides stercoralis infect humans via larvae that penetrate the skin, are carried by the blood to the lungs, then migrate to the small intestine via the trachea and oesophagus. There they become adults and attach themselves to the intestinal wall to feed and lay eggs.2,6,7
Adult hookworms can live in the human body for up to 5–7 years but they are unable to reproduce solely within a human host.6 Instead eggs are excreted in faeces, hatch in contaminated soil and then develop into larvae that can infect another person.7
In contrast, without adequate treatment S. stercoralis infection may be lifelong due to auto-infection. S. stercoralis larvae hatch from eggs while still in the intestinal tract. Some of these newly hatched larvae reinfect the host and repeat the cycle, while others are passed in the faeces. Excreted larvae can infect other people or develop into free-living adults that continue laying eggs.2
Strongyloidiasis and light hookworm infections are often asymptomatic. However, local itching and rash may occur where larvae penetrate the skin, and respiratory symptoms may occur when larvae migrate into the lungs.2,7
In heavy hookworm infections, blood loss where adult hookworms attach themselves to the intestinal wall can cause anaemia.6 Other symptoms may include abdominal pain, diarrhoea, loss of appetite, weight loss, and stunted growth and mental development.7
Auto-infective S. stercoralis larvae can disseminate throughout the body and may carry intestinal bacteria to other parts of the body.2,8 Disseminated disease is potentially fatal and poses the greatest risk to people who are immunocompromised or taking corticosteroids.8 People with disseminated disease may present with abdominal pain, distension, shock, pulmonary and neurological complications and septicaemia.2
Diagnosis and treatment
Use a single dose of albendazole to treat hookworm. Albendazole is less effective than ivermectin in treating strongyloidiasis and should be reserved for those in whom ivermectin is not recommended (Table 1).3,9
Table 1: Diagnosis and treatment of hookworm and strongyloidiasis3,7,9
Examine stool sample for eggs
Use serology: examining a stool sample is relatively insensitive
Single dose of albendazole
Adults and children > 10 kg: 400 mg dose (2 × 200 mg tablets)
Children > 6 months and < 10 kg: 200 mg
Albendazole is second choice. Use ivermectin* except in:
*200 micrograms/kg orally with fatty food; repeat 7–14 days later3,10
Ivermectin is not recommended in children < 5 years because of a lack of data.11 Refer young children with strongyloidiasis to a paediatrician or infectious-disease specialist.3 In remote areas where access to a specialist may be difficult, albendazole may be given.5 Use 200 mg once daily for 3 days if the child is < 10 kg, and 400 mg once daily for 3 days if the child is > 10 kg. Take on an empty stomach to increase intestinal absorption and repeat after 1 week.4,9
Ivermectin should not be used in people who also have Loa loa (loiasis), as there is a risk of severe encephalopathy or death in these patients.3,11 Use serology to rule out L. loa in people from West and Central Africa (where it is endemic) or in people who report episodic subcutaneous swellings or an 'eye-worm'.3 Refer people with loiasis to an infectious-disease specialist.3
The most common adverse effect is abdominal pain, reported by 1% of trial participants. Other less common side effects include diarrhoea, nausea, headache, dizziness and skin rashes.9,12
Federal government assistance for refugee health assessments
Medicare Benefits Schedule (MBS) item numbers 714 and 716 reimburse general practitioners who perform refugee and humanitarian entrant health assessments within 12 months of the patient's arrival in Australia.
Refugee health assessments should always be undertaken with an appropriate interpreter, preferably someone who is not known to the patient personally.3 The Telephone Interpreting Service (TIS) is available free of charge to general practitioners who provide a Medicare service to non-English speaking permanent residents or Australian citizens. Call the TIS Doctors' Priority Line (1300 131 450) to access this service.13
- Pharmaceutical Benefits Advisory Committee. Positive Recommendations made by the PBAC — November 2009. Canberra: Australian Government Department of Health and Ageing, 2009 http://www.health.gov.au/internet/main/publishing.nsf/Content/pbacrec-nov09-positive (accessed 11 January 2010).
- CDC Division of Parasitic Disease. Parasites and Health: strongyloidiasis. Atlanta: Centers for Disease Control and Prevention, 2008 http://www.dpd.cdc.gov/dpdx/hTML/Strongyloidiasis.htm (accessed 12 January 2010).
- Australasian Society for Infectious Diseases Refugee Health Guidelines Writing Group. Diagnosis, management and prevention of infections in recently arrived refugees. Sydney: Australasian Society for Infectious Diseases, 2009.
- Ewald D, ed. CARPA standard treatment manual reference book. 4th edn. Alice Springs: Central Australian Rural Practitioners Association, 2004.
- Central Australian Rural Practitioners Association, ed. CARPA standard treatment manual. 4th edn. Alice Springs: Central Australian Rural Practitioners Association, 2003.
- Bethony J, Brooker S, Albonico M, et al. Soil-transmitted helminth infections: ascariasis, trichuriasis, and hookworm. Lancet 2006;367:1521–32. [PubMed]
- CDC Division of Parasitic Disease. Parasites and Health: hookworm. Atlanta: Centers for Disease Control and Prevention, 2008 http://www.dpd.cdc.gov/dpdx/hTML/Hookworm.htm (accessed 12 January 2010).
- Johnston FH, Morris PS, Speare R, et al. Strongyloidiasis: a review of the evidence for Australian practitioners. Aust J Rural Health 2005;13:247–54. [PubMed]
- Rossi S, ed. Australian Medicines Handbook 2009. Adelaide: Australian Medicines Handbook Pty Ltd, 2009.
- Antibiotic Writing Group. Therapeutic Guidelines: Antibiotic. Version 13. Melbourne: Therapeutic Guidelines Ltd, 2006.
- Merck Sharp & Dohme (Australia) Pty Ltd. Stromectol product information. 28 December 2008.
- GlaxoSmithKline. Zentel product information. 15 January 2009.
- Department of Immigration and Citizenship. Free interpreting services Australian Government, 2009 http://www.immi.gov.au/living-in-australia/help-with-english/help_with_translating/free-services.htm (accessed 26 May 2009).