The efficacy and safety of three 30-day courses of albendazole in patients with neurocysticercosis

Cover Page

Cite item


Albendazole is one of the drugs indicated for the treatment of neurocysticercosis. However, data on the treatment outcome of a long course of this drug is scarce. This study aims to investigate the efficacy and safety of three 30-day courses of albendazole in patients with neurocysticercosis. Materials and methods. The diagnosis of neurocysticercosis was based on epidemiological, clinical and laboratory criteria as guided by the Vietnamese Ministry of Health. Sixty patients with a mean age of 50.17±10.03 years old, with 86.7% (95% CI: 77.8–95.5%) men, were involved in this study. Patients received three 30-day courses of albendazole with an intermittence of 20 days. Additional treatment included steroids, anticonvulsants or analgesics. Based on brain magnetic resonance imaging 6 months after the therapy, the efficacy was classified as cure (viable cysts not discernible), improvement (50% or more cysts disappeared or calcified) or inefficacy (changes in less than 50% of the cysts). The safety was determined based on the changes of biochemical parameters after each treatment course. Results. The most common clinical presentations were headache (90.0%, 95% CI: 82.2–97.8) and/or seizure (68.3%, 95% CI: 56.2–70.4), followed by other symptoms such as fainting, memory loss, and limb numbness. Active cysts were discovered in all cases and located mainly in the parenchymal region. After therapy, the rates of cure, improvement or inefficacy were 43.3% (95% CI: 30.4–56.2%), 51.7% (95% CI: 38.7–64.7%) and 5.0% (95% CI: 0–10.7%), respectively. Liver enzymes were slightly higher compared to those before therapy and mostly returned to normal ranges after drug interruption. Alanine aminotransferase levels before the 3rd course were higher than values before the first and second courses. No abnormalities in blood urea or creatinine after therapy were reported. Conclusion. Three 30-day cycles of albendazole appear to have good efficacy and tolerability in patients with neurocysticercosis.

Full Text


Cysticercosis is a disease caused by the larval stages (cysticercus) of the pork tapeworm (Taenia solium). The disease is endemic in most low- and middle-income countries and also reported in industrial countries [24]. The clinical manifestations of the disease depend on the number, location, as well as response of the body human to these cysticerci [9]. Neurocysticercosis (NCC) is the most common form of the disease and responsible for significant morbidity. Neurocysticercosis is the cause of 30% of all epilepsy cases worldwide in addition to other neurological symptoms including chronic headaches, focal neurologic deficits, intracranial hypertension, and cognitive decline [25].

Treatment of NCC is mostly symptomatic. Nevertheless, antiparasitic drugs for the destruction of cysts are important [6]. Between the two anthelmintics most commonly used, albendazole may be superior to praziquantel because of its better penetration into the central nervous system, lower cost, and lesser interaction with other drugs [19]. Several studies have investigated the efficacy of albendazole, and a dose of 15 mg/kg/day has generally been accepted [2, 3, 10, 11, 12]. However, there is still considerable disagreement concerning the length of therapy. Most studies have relied on a one to four-week course, with observed cyst disappearance in 25% to 37% of case [2, 3, 10, 11, 12]. Due to the low efficacy of this regime, a longer duration (more than one 4-week course) might be an appropriate approach, but there is little information on the treatment outcome of this prolonged regime [17]. This study aims to investigate the efficacy and safety of three 30-day courses of albendazole in patients with NCC.

Materials and methods

Ethical consideration. This research is part of thesis work for the fulfilment of Doctor of Philosophy in Health Studies. It obtained clearance from the ethics committee of the Vietnam National Institute of Malariology, Parasitology and Entomology (NIMPE). Written or verbal consent was obtained from all the patients or their legal representatives.

Study design. This prospective study was carried out at the Specialized Parasitic Clinic, NIMPE during January 2017 and December 2020. All patients visiting the clinic with clinical symptoms/signs suspected of NCC were screened for the infection. Criteria for inclusion were subjects more than five years old and diagnosed with NCC, with willingness to complete antiparasitic therapy and follow-up examination after treatment. Criteria for exclusion were pregnant women, subjects exhibiting acute diseases or concurrent parasitic diseases, or having a known history of allergy to benzimidazole.

After informed consent was obtained, a detailed history of symptoms, duration and progression of the disease, in addition to sociodemographic data, was recorded. A careful systemic and neurologic examination was done, followed by laboratory investigations. Blood examination included blood cell counts and standard tests of biochemistry. Serum enzyme-linked immunosorbent assay (ELISA) for certain infections common in Vietnam (cysticercosis, fascioliasis, strongyloidiasis, gnathostomiasis, toxocariasis, amebiasis) was performed using reagents from Cortez Diagnostics Inc. (USA) following manufacturer instructions. Brain magnetic resonance imaging (MRI) was used to determine the number and stages of cysts. Stool samples were collected and examined for intestinal helminths or protozoans.

The treatment. Patients with vesicular, colloidal, or granular cysts on MRI received three 30-day courses of albendazole at a daily dose of 15 mg/kg of body weight. The intermittence between the courses was 20 days. Before taking albendazole, patients received praziquantel 20 mg/kg to treat adult worms [22]. Additional treatment included steroids to decrease inflammation and anticonvulsant or analgesic drugs as needed.

Follow-up. Clinical assessment was performed at the start of and during therapy. Blood samples were taken at the beginning and the end of all three courses. Brain MRI was performed 6 months after completion of therapy to assess treatment outcome.

Definition. As guided by the Vietnamese Ministry of Health, diagnosis of cysticercosis was based on epidemiological, clinical, and laboratory criteria based on well-known ones [4, 5]. Epidemiologic criteria include ingestion of raw vegetables or living in endemic areas. Suggestive manifestations of NCC are late-onset seizures, focal neurologic deficits, intracranial hypertension, chronic headaches, or cognitive decline. Laboratory criteria are: (1) positive biopsy results of cysts; (2) pathognomonic lesions on computed tomography (CT) or MRI (cysts with “hole-with-dot” appearance); (3) parasites discovered by funduscopic examination; and (4) a positive result by serum ELISA [22]. On MRI, location of cysts was grouped into cortex/subcortex, hemisphere, subarachnoid, or intraventricular. Based on stage, they were classified as viable (vesicular, colloidal, granular) or dead (calcified) cysts [7, 26]. Treatment outcome was classified based on the resolution of cystic lesions as follows: complete resolution/cure wherein viable cysts were not discernible on MRI; partial resolution/improvement wherein 50% or more cysts disappeared or calcified; or no resolution/inefficacy wherein changes were reported in less than 50% of the cysts. Reference ranges were: 1–35 U/L for aspartate aminotransferase (AST) and alanine aminotransferase (ALT); 1.8–7.1 mmol/L for urea; and 44–97 μmol/L (female) and 53–106 μmol/L (male) for creatinine [23]. Mild elevation was designated as liver enzyme levels less than five times the upper limit of the normal value. Greater than 15 times the upper limit was designated as severe elevation.

Statistical analysis. Data analysis was performed with SPSS 16.0 (SPSS-IBM Company). Categorical variables were expressed as case number (n) and percentages, while numerical variables were expressed as mean and standard deviation (±SD). A paired sample t-test was used to determine the mean difference of continuous variables at different time points. P-values less than 0.05 were considered statistically significant.


Sixty patients aged between 28–68 years participated in the study. The male to female ratio was 6.5/1. All patients met the epidemiologic criteria due to a history of eating raw vegetables in addition to living in north and central Vietnam where active transmission of taeniasis and cysticercosis has been reported. The most common clinical presentations were headache and/or seizure, followed by other symptoms such as fainting, memory loss, or limb numbness. Only one patient had a history of defecating proglottides or subcutaneous cysts. On brain MRI, cysts were located in different locations, but mainly in the parenchymal region (cerebral hemisphere (83.3%), cortical/subcortical region (41.7%), or cerebellum (10.0%). Multiple cysts (≥ 2) were discovered in 48/50 (96%) cases in the hemisphere, 14/25 (56%) cases in cortical/subcortical regions, and 3/6 (50%) cases in the cerebellum. In the intraventricular or subarachnoid region, only a single cyst was discovered. Vesicular cysts occurred in 60 (100%) cases, and calcified cysts in one case (cerebellum). Elevation of AST occurred in 19 (31.7%) patients and of ALT in 24 (40.0%) patients. Average liver enzyme levels were slightly higher than normal reference, whereas the levels of urea and creatinine were within the normal ranges (Table 1).


Table 1. Baseline patient characteristics (n = 60)



% (95% CI)

Age (years, X±SD)





13.3 (4.8–22.2)



86.7 (77.8–95.5)




65.5 (52.6–77.4)

Other jobs


35.5 (22.6–47.4)




90.0 (82.2–97.8)



68.3 (56.2–70.4)

Memory loss


19.2 (12.3–34.4)



28.3 (16.6–40.1)

Limb numbness


20.0 (9.6–30.4)

Vomiting, nausea


15.0 (5.7–24.3)

Balance disorders


10.0 (2.2–17.8)

Muscle weakness


10.0 (2.2–17.8)

Blurred vision


3.3 (0.1–8.0)

Cyst site*



83.3 (73.6–93.0)

Cortical/ subcortical


41.7 (28.8–54.4)



10.0 (2.2–17.8)



1.7 (0–0.5)

Subarachnoid spaces


1.7 (0–0.5)

Biochemical parameters





Urea (mmol/L, X±SD)


Creatinine (mmol/L, X±SD)


Note. *Same patients with cysts at different sites.


After antiparasitic therapy, almost all (95.0%) patients had radiological improvement, but a complete resolution was reported in less than half of the participants (43.3%). There were two patients with no cystic resolution, and one patient showed an increase in the number of cysts six months after treatment (Table 2). Clinical examination showed that 23/41 (56.1%) patients with seizures were completely cured, and 25/54 (46.3%) patients having headaches recovered. Of the patients with loss of memory or fainting, the rates of complete recovery were (6/14) 42.9% and (11/17) 64.7%, respectively.


Table 2. Efficacy of antiparasitic treatment (n = 60)



% (95% CI)



43.3 (30.4–56.2)



51.7 (38.7–64.7)



5.0 (0–10.7)


Table 3 shows changes in biochemical parameters after treatment. The levels of liver enzymes after treatment were all above the normal ranges and significantly higher compared to those before the antiparasitic course. The percentages of patients with increased AST after the 1st, 2nd and 3rd course were 66.7%, 75% and 85% respectively. There were 50 (83.3%), 55 (91.7%), and 49 (81.7%) cases having elevated ALT levels after the first, second, and third course. Most of them had mild or moderate elevation; only one patient had a severe elevation of liver enzymes. After drug interruption, liver enzyme levels mostly returned to normal ranges equivalent to pretreatments levels. However, ALT levels before the 3rd course were higher than the baseline as well as the normal range. Urea and creatinine concentrations were within normal limits at all examinations. The only exception was that urea concentration after the 2nd and 3rd course increased slightly compared to levels before the course but was within normal ranges. During therapy, some patients developed headaches, vomiting, or exacerbation of seizures.


Table 3. Biochemical parameters before and after therapy (n = 60)
































Urea (mmol/L, X±SD)













Creatinine (mmol/L, X±SD)













Note. *The mean ALT concentration before the third course was higher than that before the first and the second course (p < 0.001).



This study was carried out to investigate the efficacy and safety of a prolonged regime of albendazole in patients with NCC. Our results suggest that three 30-day cycles of albendazole have good efficacy against NCC. Most of the patients (95%) had radiological improvement, and a complete clearance of cysts on MRI was reported in 43.3% of cases. Clinical examination showed that about half of the patients had improvement, but these results were not included in the efficacy evaluation. Clinical evaluation has been considered inappropriate because some symptoms, such as seizures, can present long after cyst clearance [7, 9]. The complete resolution rate in our patients (43.3%) was slightly higher than that in previous observations (reporting cure rates ranging from 25% to 37%) [2, 3, 10, 11]. This difference in the efficacy could be due to the longer duration of therapy (90 days) in our study compared to previously cited studies (7–28 days) [2, 3, 10, 11]. Some authors have reported that a long duration of albendazole may have no additional benefit compared to the short ones [15, 20]. Nevertheless, Garcia et al. (1997) noted a significant difference in the number of cysts persisting at day 360 among patients taking a short (7-day) and long (14-day) schedule of albendazole [8]. An overly-short duration (one week) may not change the natural course of NCC [16]. Our results are supported by another observation [17] and suggest that an extension of the duration of albendazole therapy may be a good choice for patients with NCC.

Results of safety assessment showed that this prolonged regime of albendazole seems to have a favorable safety profile. Liver enzymes were only mildly and temporarily elevated, while urea and creatinine concentrations were within normal limits. The proportion of patients with elevated liver enzymes in our study (> 80%) was far higher than that usually reported in those taking albendazole (10–20%) [14]. A possible reason for this difference was the high rate of patients with increased liver enzymes before therapy (Table 1). Another reason could be the prolonged use of albendazole (90 days) compared to short courses (7–28 days) used in most previous studies [2, 3, 10, 11]. Although a high rate of patients with elevated liver enzymes was seen, the proportion of severe elevation was low (1.7%); this is in agreement with a scarcity of reported cases of albendazole-induced liver injury [1, 13, 18]. The unchanged levels of urea and creatinine in our patients are similar to other results [17]. During therapy, some patients developed headaches, vomiting, or exacerbation of seizures. These manifestations could be adverse reactions or predictors of drug effectiveness, so they are not included in safety assessments [21].

Some limitations remain in our study. There were only a small number of patients willing to complete treatment and undergo final assessment six months after therapy, so the small sample size is unavoidable. A control group taking placebo drugs is lacking as this is not acceptable practice in our country.


Three 30-day cycles of albendazole appear to have favorable outcomes in patients with neurocysticercosis. Almost all patients had an improvement in cystic lesions and the rate of complete disappearance is encouraging. This regime has good tolerability, but monitoring of liver transaminase levels is critical.

Conflict of interest

The authors declare that they have no conflict of interests.


About the authors

C. T. Sinh

Vinh Medical University


Associate Professor, MD, PhD, Department of Internal medicine

Viet Nam, Nghe An

T. T. Thang

Nghe An Eye Hospital


Department of Medical examination

Viet Nam, Nghe An

T. D. Thang

Thai Thuong Hoang Hospital


MD, Department of Internal medicine

Viet Nam, Nghe An

C. B. Loi

National Institute of Malaria, Parasitology and Entomology


Associate Professor, MD, PhD, Scientific and Training Management Department

Viet Nam, 160 Phung Hung, Ha Dong, Ha Noi

L. T. Anh

Vietnam Military Medical University

Author for correspondence.
ORCID iD: 0000-0002-4919-1739

Associate Professor, MD, PhD, Department of Parasitology

Viet Nam, 160 Phung Hung, Ha Dong, Ha Noi


  1. Bilgic Y., Yilmaz C., Cagin Y.F., Atayan Y., Karadag N., Harputluoglu M.M.M. Albendazole induced recurrent acute toxic hepatitis: a case report. Acta Gastroenterol. Belg., 2017, vol. 80, no. 2, pp. 309–311.
  2. Carpio A., Kelvin E.A., Bagiella E., Leslie D., Leon P., Andrews H., Hauser W.A., Effects of albendazole treatment on neurocysticercosis: a randomised controlled trial. J. Neurol. Neurosurg. Psychiatry, 2008, vol. 79, no. 9, pp. 1050–1055. doi: 10.1136/jnnp.2008.144899
  3. Carpio A., Santillán F., León P., Flores C., Hauser, W.A. Is the course of neurocysticercosis modified by treatment with anthelmintic agents? Arch. Intern. Med., 1995, vol. 155, no. 18, pp. 1982–1988.
  4. Del Brutto O.Н., Nash T.E., White A.C. Jr., Rajshekhar V., Wilkins P.P., Singh G., Vasquez C.M., Salgado P., Gilman R.H., Garcia H.H. Revised diagnostic criteria for neurocysticercosis. J. Neurol. Sci., 2016, vol. 372, pp. 202–210. doi: 10.1016/j.jns.2016.11.045
  5. Del Brutto O.H., Rajshekhar V., White A.C. Jr., Tsang V.C., Nash T.E., Takayanagui O.M., Schantz P.M., Evans C.A., Flisser A., Correa D., Botero D., Allan J.C., Sarti E., Gonzalez A.E., Gilman R.H., García H.H. Proposed diagnostic criteria for neurocysticercosis. Neurology, 2001, vol. 57, no. 2, pp. 177–183. doi: 10.1212/wnl.57.2.177
  6. Fogang Y.F., Savadogo A.A., Camara M., Toffa D.H., Basse A., Sow A.D., Ndiaye M.M. Managing neurocysticercosis: challenges and solutions. Int. J. Gen. Med., 2015, vol. 8, pp. 333–344. doi: 10.2147/IJGM.S73249
  7. García H.H., Del Brutto O.H. Imaging findings in neurocysticercosis. Acta Trop., 2003, vol. 87, no. 1, pp. 71–78. doi: 10.1016/s0001-706x(03)00057-3
  8. Garcia H.H., Gilman R.H., Horton J., Martinez M., Herrera G., Altamirano J., Cuba J.M., Rios-Saavedra N., Verastegui M., Boero J., Gonzalez A.E. Albendazole therapy for neurocysticercosis. Neurology, 1997, vol. 48, no. 5, pp. 1421–1427. doi: 10.1212/wnl.48.5.1421
  9. García H.H., Gonzalez A.E., Evans C.A.W., Gilma, R.H. Taenia solium cysticercosis. Lancet, 2003, vol. 362, no. 9383, pp. 547–556. doi: 10.1016/S0140-6736(03)14117-7
  10. Garcia H.H., Gonzales I., Lescano A.G., Bustos J.A., Zimic M., Escalante D., Saavedra H., Gavidia M., Rodriguez L., Najar E., Umeres H., Pretell E.J. Efficacy of combined antiparasitic therapy with praziquantel and albendazole for neurocysticercosis: a double-blind, randomised controlled trial. Lancet. Infect. Dis., 2014, vol. 14, no. 8, pp. 687–695. doi: 10.1016/S1473-3099(14)70779-0
  11. Garcia H.H., Lescan, A.G., Gonzales I., Bustos J.A., Pretell E.J., Horton J., Saavedra H., Gonzalez A.E., Gilman R.H. Cysticidal efficacy of combined treatment with praziquantel and albendazole for parenchymal brain cysticercosis. Clin. Infect. Dis., 2016, vol. 62, no. 11, pp. 1375–1379. doi: 10.1093/cid/ciw134
  12. Garcia H.H., Pretell E.J., Gilman R.H., Martinez S.M., Moulton L.H., Del Brutto O.H., Herrera G., Evans C.A.W., Gonzalez A.E. A trial of antiparasitic treatment to reduce the rate of seizures due to cerebral cysticercosis. N. Engl. J. Med., 2004, vol. 350, no. 3, pp. 249–258. doi: 10.1056/NEJMoa031294
  13. Hong S.T. Albendazole and praziquantel: review and safety monitoring in Korea. Infect. Chemother., 2018, vol. 50, no. 1, pp. 1–10. doi: 10.3947/ic.2018.50.1.1
  14. Horton R. Albendazole in treatment of human cystic echinococcosis: 12 years of experience. Acta Trop., 1997, vol. 64, no. 1–2, pp. 79–93. doi: 10.1016/s0001-706x(96)00640-7
  15. Johnson N., Saini A.G., Malhi P., Khandelwal N., Singhi P. Comparison of long-term outcomes between 7 days and 28 days albendazole monotherapy in the treatment of single-lesion neurocysticercosis in children. J. Child Neurol., 2021, vol. 37, no. 1, pp. 28–34. doi: 10.1177/08830738211035864
  16. Padma M., Behari M., Misra N., Ahuja G. Albendazole in neurocysticercosis. Natl Med. J. India., 1995, vol. 8, no. 6, pp. 255–258.
  17. Pandey S., Malhotra H.S., Garg R.K., Malhotra K.P., Kumar N., Rizvi I., Jain A., Kohli N., Verma R., Sharma P., Uniyal R., Pandey S. Quantitative assessment of lesion load and efficacy of 3 cycles of albendazole in disseminated cysticercosis: a prospective evaluation. BMC Infect. Dis., 2020, vol. 20, no. 1: 220. doi: 10.1186/s12879-020-4891-5
  18. Piloiu C., Dumitrascu D.L. Albendazole-induced liver injury. Am. J. Ther., 2021, vol. 28, no. 3, pp. e335–e340. doi: 10.1097/MJT.0000000000001341
  19. Singhi P. Neurocysticercosis. Ther. Adv. Neurol. Disord., 2011, vol. 4, no. 2, pp. 67–81. doi: 10.1177/1756285610395654
  20. Singhi P., Dayal D., Khandelwal N. One week versus four weeks of albendazole therapy for neurocysticercosis in children: a randomized, placebo-controlled double blind trial. Pediatr. Infect. Dis. J., 2003, vol. 22, no. 3, pp. 268–272. doi: 10.1097/01.inf.0000055095.84136.a2
  21. Sotelo J., Del Brutto O.H., Penagos P.J., Escobedo F., Torres B., Rodríguez-Carbajal J., Rubio-Donnadieu F. Comparison of therapeutic regimen of anticysticercal drugs for parenchymal brain cysticercosis. J. Neurol., 2004, vol. 237, no. 2, pp. 69–72. doi: 10.1007/BF00314663
  22. The Ministry of Health. The Guidelines for the diagnosis and treatment of clonorchiasis/opisthorchiasis, paragonimiasis, taeniasis and cysticercosis (Decision 1450/2004/QD-BYT) [in Vietnamese]. 2004.
  23. Walker H., Hall W., Hurst J. (eds.). Clinical Methods: The history, physical, and laboratory examinations. Boston: Butterworths, 1990. 1087 p.
  24. WHO, Landscape analysis: management of neurocysticercosis with an emphasis on low- and middle-income countries (WHO/HTM/NTD/NZD/2015.05). Geneva: World Health Organization, 2015. 62 p.
  25. WHO. Taeniasis/cysticercosis, key facts. World Health Organization, 2022. URL:,also%20become%20infected%20with%20T (12.09.2022)
  26. Zhao J.-L., Lerner A., Shu Z., Gao X.-J., Zee C.-S. Imaging spectrum of neurocysticercosis. Radiol. Infect. Dis. 2015, vol. 1, no. 2, pp. 94–102. doi: 10.1016/j.jrid.2014.12.001

Supplementary files

There are no supplementary files to display.

Copyright (c) 2022 Sinh C.T., Thang T.T., Thang T.D., Loi C.B., Anh L.T.

Creative Commons License
This work is licensed under a Creative Commons Attribution 4.0 International License.

СМИ зарегистрировано Федеральной службой по надзору в сфере связи, информационных технологий и массовых коммуникаций (Роскомнадзор).
Регистрационный номер и дата принятия решения о регистрации СМИ: серия ПИ № ФС 77 - 64788 от 02.02.2016.

This website uses cookies

You consent to our cookies if you continue to use our website.

About Cookies