Toxocariasis Medication

  • Author: Sun Huh, MD, PhD; Chief Editor: Mark R Wallace, MD, FACP, FIDSA  more...
Updated: Feb 16, 2016

Medication Summary

In general, blood eosinophilia combined with a positive serologic test result indicates active toxocariasis and requires treatment. Deciding whether to treat covert or subclinical toxocariasis that does not show eosinophilia is controversial. Consider treatment in patients with a total serum IgE level over 500 IU/mL. Mebendazole or diethylcarbamazine kills the nematode larvae. Prednisone can be used as an adjunct to antihelminthic therapy in patients with wheezing or other signs of tissue inflammation.



Class Summary

These agents are specific to nematode infection.

Mebendazole (Vermox)


DOC. Adverse effects are negligible, except headaches during early therapy. These symptoms are from metabolites secreted from nematodes that are killed by the drug. Causes worm death by selectively and irreversibly blocking uptake of glucose and other nutrients in susceptible adult intestines where helminths dwell.

Albendazole (Albenza)


Second DOC if mebendazole is difficult to obtain. Decreases ATP production in the worm, causing energy depletion, immobilization, and, finally, death.

Diethylcarbamazine citrate (Hetrazan)


Synthetic organic compound highly specific for several common parasites. Does not contain any toxic metallic elements. Not recommended as the DOC because of more severe adverse effects. Recommended if therapy with mebendazole fails or mebendazole is not available.

Contributor Information and Disclosures

Sun Huh, MD, PhD Chairman, Professor, Department of Parasitology, College of Medicine, Hallym University, Korea

Disclosure: Nothing to disclose.


Soo-Ung Lee, PhD Manager, Research and Development, Chuncheon Bioindustry Foundation, Korea

Disclosure: Nothing to disclose.

Specialty Editor Board

Francisco Talavera, PharmD, PhD Adjunct Assistant Professor, University of Nebraska Medical Center College of Pharmacy; Editor-in-Chief, Medscape Drug Reference

Disclosure: Received salary from Medscape for employment. for: Medscape.

Gordon L Woods, MD Consulting Staff, Department of Internal Medicine, University Medical Center

Gordon L Woods, MD is a member of the following medical societies: Society of General Internal Medicine

Disclosure: Nothing to disclose.

Chief Editor

Mark R Wallace, MD, FACP, FIDSA Clinical Professor of Medicine, Florida State University College of Medicine; Clinical Professor of Medicine, University of Central Florida College of Medicine

Mark R Wallace, MD, FACP, FIDSA is a member of the following medical societies: American College of Physicians, American Medical Association, American Society for Microbiology, Infectious Diseases Society of America, International AIDS Society, Florida Infectious Diseases Society

Disclosure: Nothing to disclose.

Additional Contributors

Pranatharthi Haran Chandrasekar, MBBS, MD Professor, Chief of Infectious Disease, Program Director of Infectious Disease Fellowship, Department of Internal Medicine, Wayne State University School of Medicine

Pranatharthi Haran Chandrasekar, MBBS, MD is a member of the following medical societies: American College of Physicians, American Society for Microbiology, International Immunocompromised Host Society, Infectious Diseases Society of America

Disclosure: Nothing to disclose.

  1. Ahn SJ, Ryoo NK, Woo SJ. Ocular toxocariasis: clinical features, diagnosis, treatment, and prevention. Asia Pac Allergy. 2014 Jul. 4(3):134-41. [Medline]. [Full Text].

  2. Moreira GM, Telmo PD, Mendonça M, Moreira AN, McBride AJ, Scaini CJ, et al. Human toxocariasis: current advances in diagnostics, treatment, and interventions. Trends Parasitol. 2014 Sep. 30(9):456-464. [Medline].

  3. Centers for Disease Control and Prevention. Ocular toxocariasis--United States, 2009-2010. MMWR Morb Mortal Wkly Rep. 2011 Jun 10. 60(22):734-6. [Medline].

  4. Nelson S, Greene T, Ernhart CB. Toxocara canis infection in preschool age children: risk factors and the cognitive development of preschool children. Neurotoxicol Teratol. 1996 Mar-Apr. 18(2):167-74. [Medline].

  5. Chomel BB, Kasten R, Adams C, et al. Serosurvey of some major zoonotic infections in children and teenagers in Bali, Indonesia. Southeast Asian J Trop Med Public Health. 1993 Jun. 24(2):321-6. [Medline].

  6. Magnaval JF, Michault A, Calon N, et al. Epidemiology of human toxocariasis in La Réunion. Trans R Soc Trop Med Hyg. 1994 Sep-Oct. 88(5):531-3. [Medline].

  7. Lee RM, Moore LB, Bottazzi ME, Hotez PJ. Toxocariasis in north america: a systematic review. PLoS Negl Trop Dis. 2014 Aug. 8(8):e3116. [Medline]. [Full Text].

  8. CDC. CDC Guidelines for Veterinarians: Prevention of Zoonotic Transmission of Ascarids and Hookworms of Dogs and Cats. Available at

  9. CDC. Centers for Disease Control and Prevention (CDC). Available at

  10. Choi D, Lim JH, Choi DC, et al. Transmission of Toxocara canis via Ingestion of Raw Cow Liver: A Cross-Sectional Study in Healthy Adults. Korean J Parasitol. 2012 Mar. 50(1):23-7. [Medline]. [Full Text].

  11. Choi D, Lim JH, Choi DC, Paik SW, Kim SH, Huh S. Toxocariasis and ingestion of raw cow liver in patients with eosinophilia. Korean J Parasitol. 2008 Sep. 46(3):139-43. [Medline]. [Full Text].

  12. Congdon P, Lloyd P. Toxocara infection in the United States: the relevance of poverty, geography and demography as risk factors, and implications for estimating county prevalence. Int J Public Health. 2011 Feb. 56(1):15-24. [Medline].

  13. Iddawela RD, Rajapakse RP, Perera NA, et al. Characterization of a Toxocara canis species-specific excretory-secretory antigen (TcES-57) and development of a double sandwich ELISA for diagnosis of visceral larva migrans. Korean J Parasitol. 2007 Mar. 45(1):19-26. [Medline].

  14. Kwon SI, Lee JP, Park SP, Lee EK, Huh S, Park IW. Ocular toxocariasis in Korea. Jpn J Ophthalmol. 2011 Mar. 55(2):143-7. [Medline].

  15. Lee SU, Yu JR, Huh S. Ultrastructural localization of Toxocara canis larval antigen reacted with a seropositive human serum. Korean J Parasitol. 2009 Mar. 47(1):65-8. [Medline]. [Full Text].

  16. Magnaval JF. Comparative efficacy of diethylcarbamazine and mebendazole for the treatment of human toxocariasis. Parasitology. 1995 Jun. 110 (Pt 5):529-33. [Medline].

  17. Magnaval JF, Fabre R, Maurieres P, et al. Application of the western blotting procedure for the immunodiagnosis of human toxocariasis. Parasitol Res. 1991. 77(8):697-702. [Medline].

  18. Magnaval JF, Fabre R, Maurieres P, et al. Evaluation of an immunoenzymatic assay detecting specific anti-Toxocara immunoglobulin E for diagnosis and posttreatment follow-up of human toxocariasis. J Clin Microbiol. 1992 Sep. 30(9):2269-74. [Medline].

  19. Magnaval JF, Glickman LT, Dorchies P, et al. Highlights of human toxocariasis. Korean J Parasitol. 2001 Mar. 39(1):1-11. [Medline].

  20. Magnaval JF, Malard L, Morassin B, et al. Immunodiagnosis of ocular toxocariasis using Western-blot for the detection of specific anti-Toxocara IgG and CAP for the measurement of specific anti-Toxocara IgE. J Helminthol. 2002 Dec. 76(4):335-9. [Medline].

  21. Moiyadi A, Mahadevan A, Anandh B, et al. Visceral larva migrans presenting as multiple intracranial and intraspinal abscesses. Neuropathology. 2007 Aug. 27(4):371-4. [Medline].

  22. Muñoz-Guzmán MA, del Río-Navarro BE, Valdivia-Anda G, Alba-Hurtado F. The increase in seroprevalence to Toxocara canis in asthmatic children is related to cross-reaction with Ascaris suum antigens. Allergol Immunopathol (Madr). 2010 May-Jun. 38(3):115-21. [Medline].

  23. Oryan A, Sadjjadi SM, Azizi S. Longevity of Toxocara cati larvae and pathology in tissues of experimentally infected chickens. Korean J Parasitol. 2010 Mar. 48(1):79-80. [Medline]. [Full Text].

  24. Park HY, Lee SU, Huh S, et al. A seroepidemiological survey for toxocariasis in apparently healthy residents in Gangwon-do, Korea. Korean J Parasitol. 2002 Sep. 40(3):113-7. [Medline].

  25. Park SP, Huh S, Magnaval JF, et al. A case of presumed ocular toxocariasis in a 28-year old woman. Korean J Ophthalmol. 1999 Dec. 13(2):115-9. [Medline].

  26. Park SP, Park I, Park HY, et al. Five cases of ocular toxocariasis confirmed by serology. Korean J Parasitol. 2000 Dec. 38(4):267-73. [Medline].

  27. Smith HV. Antibody reactivity in human toxocariasis. Lewis JW, Maizels RM, eds. Toxocara and Toxocariasis: Clinical, Epidemiological, and Molecular Perspectives. London: Institute of Biology and the British Society for Parasitology; 1993. 91-109.

  28. Sun T, Bellosa ML, Lucio-Forster A, et al. A comparison of the protein constituents of the major body compartments of the dog roundworm, Toxocara canis. Vet Parasitol. 2007 Nov 30. 150(1-2):111-5. [Medline].

  29. Won K, Kruszon-Moran D, Schantz P, et al. Abstract of the 56th American Society of Tropical Medicine and Hygiene. National seroprevalence and risk factors for zoonotic Toxocara spp. infection. Philadelphia, Pennsylvania; Nov 4-8, 2007.

  30. Won KY, Kruszon-Moran D, Schantz PM, Jones JL. National seroprevalence and risk factors for Zoonotic Toxocara spp. infection. Am J Trop Med Hyg. 2008 Oct. 79(4):552-7. [Medline]. [Full Text].

The image on the left is a posteroanterior chest radiograph in a patient with toxocariasis. The image on the right is a CT scan of the patient with toxocariasis showing multiple pulmonary nodules with surrounding ground-glass opacities at first visit.
Funduscopic examination of the right eye of a patient with ocular toxocariasis showing rhegmatogenous retinal detachment.
Immunogold finding of Toxocara canis larva reacted with a seropositive human serum. Arrows indicate each particle. (A) High-density immunogold particles are distributed in the large columnlike secretory cell (LCSC), excretory duct (ED), and cuticle(C); (B) high-density immunogold particles are shown in the secretory cell (SC), excretory duct (ED), and cuticle; (C) immunogold particles are distributed in the excretory duct (ED); (D) high-density particles are displayed in the microvilli of the intestine (MI); (E) immunogold particles are shown in the excretory duct; and (F) high-density immunogold particles are distributed in the cuticle(C).
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