Vermox
The effects of mebendazole on P4501A activity in rat hepatocytes and HepG2 cells. Comparison with tiabendazole and omeprazole.

Baliharova V, Skalova L, Maas RF, De Vrieze G, Bull S, Fink-Gremmels J.

Faculty of Pharmacy, Charles University, Heyrovskeho 1203, CZ-50005 Hradec Kralove, Czech Republic. 95bav3361 faf.cuni.cz

Mebendazole is a benzimidazole anthelmintic widely used in veterinary and human therapy. Among benzimidazole derivatives, several drugs with inducing effect on cytochromes P450 can be found. However, the induction capacity of mebendazole on P450s has not been explored yet. In this study, the effects of mebendazole on P4501A activity was tested in primary cultures of rat hepatocytes and in human hepatoma HepG2 cell line. Two known P4501A inducers with benzimidazole structure, tiabendazole and omeprazole, were also included in the experiments with the aim of studying structure-induction relationships. After 24-, 48- and 72-h incubation of rat hepatocytes and HepG2 cells with drugs in various concentrations (0.1-100 microM), enzyme activity associated with P4501A1/2 (EROD, MROD) was measured. In addition, the P4501A1/2 protein levels in both in-vitro systems were determined by Western-blotting. Mebendazole provoked a significant increase in P4501A1/2 protein expression and P4501A activity in both in-vitro systems. Omeprazole caused a significant dose-dependent increase of P4501A activity only in HepG2 cells. Although tiabendazole treatment led to significant increase of P4501A protein level, no effect on P4501A activity was observed in either system. The results demonstrate that mebendazole possesses the ability to significantly induce P4501A. Thus, pharmacological and toxicological consequences of P4501A induction should be taken into account in human therapy. The structure-induction relationships and differences between in-vitro systems used are discussed.

Online source: www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=12841937&dopt=Abstract mebendazole Vermox



Vermox
Effect of anthelmintics on the early stage of Enterobius vermicularis.

Cho SY, Kang SY, Kim SI, Song CY.

Department of Parasitology, College of Medicine, Chung-Ang University, Seoul, Korea.

In order to determine the susceptible age of Enterobius vermicularis to anthelmintics and to observe the chronologic growth of female E. vermicularis in man, experimental infections were done. About 500 eggs were challenged to 19 volunteers. After 4, 8, 16, 20, 24, 28, 32 and 35 days of infection, each case was treated by either mebendazole or pyrantel pamoate. On the 40th day of infection all cases including control were treated again to terminate the expermental infection and to evaluate the effect of previous treatment. Each case collected 3-day stools to harvest the expelled worms. The results could be summarized as follows: The infection rates of females were in range of 0.6~13.1% in control cases. Because the collected worms showed comparable growth and development by day, the worns were concluded to be derived from experimental infection. Cases that were treated with mebendazole on 4, 8 and 16 days after infection expelled 37.5%, 2.5% and 67.5% of the number expelled by a control case on the 40th day. Cases treated thereafter expelled no worms on the 40 days. Cases that were treated with pyrantel pamoates on 4, 8, 16, 24, 28, 32 and 35 days, expelled 90.7%, 25%, 45.3%, 8%, 2.7%, 5% and 29.3% of the number collected from control cases in respect. All the worms collected were females. The total body length increased consistently and comparably from the 20th day of infection. Those collected on the 20th day were 2.5~3.0 mm long with vigina, sac-like structure and strands of ovaries; 24 day-old worms may have short uterus, 28 day-old worms had long uterus without eggs, 32 day-old worms began to produce eggs, 35 day-old worms showed wide variations in egg deposit in uterus, and 40 day-old worms had uterus filled with eggs from vulva to anal levels. From the above results, it was inferred that the life span of female Enterobius vermicularis was longer than 40 days, and the developmental stages of worms younger than 16 days resisted considerably to both mebendazole and pyrantel pamoate.

Online source: www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=12888681&dopt=Abstract mebendazole Vermox



Vermox
Efficacy Of Mebendazole In Treatment And Control Of Trichuriasis In Korea.

Seo BS, Lee SH, Chai JY, Hong ST, Hong SJ.

Department of Parasitology and Institute of Endemic Diseases, College of Medicine, Seoul National University, Korea.

Mebendazole was tested for its efficacy in individual treatment and mass control of Trichuris trichiura infection in Korea. The results were as follows: 1. The efficacy of mebendazole in 430 cases 3 weeks after treatment with mebendazole(100-1,200 mg) was not so satisfactory (15.0-64.0 and 24.6-95.2% in cure and egg reduction rates respectively). But it was observed that the higher the total dose of the drug the better the efficacy. 2. The egg positive rate of the inhabitants in mass control programme by 600 mg mebendazole decreased form 40.0 to 5.6 % during one year, May 1982-May 1983, by repeated blanket mass chemotherapy every 3 months (in conventional regimen), while the decrease was less marked or unrecognizable in 3-month (signle or two divided doses), 6-month, 12-month interval and placebo control groups. From the results, it was concluded that, although mebendazole was not highly effective in individual treatment of T. trichiura infection, it was fairly useful in mass cotrol, by repeated mass chemotherapy every 3 months.

Online source: www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=12902674&dopt=Abstract mebendazole Vermox



Vermox
Morphological Observation Of Enterobius Vermicularis Expelled By Various Anthelmintics.

Cho SY, Hong ST, Kang SY, Song CY.

Department of Parasitology, College of Medicine, Chung-Ang University, Korea.

When enterobiasis cases were treated with anthelmintics only for one time, the interval to recurrence was variable by different drugs used. And this phenomenon is supposedly connected with biological or developmental cycle of the worm and the consequent efficacy of the different anthelmintics. This study was undertaken to confirm this fact by studying the expelled worms morphologically to correlate the anthelmintics efficacy and stage of worm development in Enterobius vermicularis. A total of 131 children in 3 orphanages was examined by 4 anal swabs (mean positive rate, 80%). They were randomized into 5 experimental groups. Each group was treated with placebo, mebendazole, pyrantel, pyrvinium, and piperazine (70 mg/kg, single dose) respectively. After treatment, all stool were collected for 3 days to get the expelled Enterobius. A total of 6,165 pinworms was studied under the microscope. The sex was discriminated and the length was individually measured. A number of male pinworms was collected in all groups. Females of 2~11 mm in length were also collected in 5 groups. However, significantly larger number of short females was observed in mebendazole group compared with other groups. Twenty-one days after the first treatment, all children were again treated with mebendazole. Once more stool were examined. A total of 1,853 worms was collected. In mebendazole group, there were no females longer than 8.74 mm in the second treatment. In pyrvinium group, 8.31mm in lenght was the longest for female. However in control, pyrantel and piperazine groups, females of 2~11 mm in length were collected. From above results, one could conclude that the removing ability of mebendazole and pyrvinium was satisfactory for the worms in the early stage of development in Enterobius. Pyrantel and single dose of piperazine showed less effective in worm reduction ability especially on those at the early stages.

Online source: www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=12902715&dopt=Abstract mebendazole Vermox



Vermox
Reduced Single Dose Of Mebendazole In Treatment Of Ascaris Lumbricoides Infection.

Seo BS, Cho SY, Chai JY.

Department of Parasitology and Institute of Endemic Diseases, College of Medicine, Seoul National University, Korea.

The efficacy of reduced single doses of mebendazole against Ascaris lumbricoides infection was evaluated by cellophane thick smear and egg counting techinques, in two rural populations from December 1977 to March 1978. Total 191 infected cases were divided into five dose groups; 100 mg single dose, 200 mg single dose, 300 mg single dose, 400 mg and 600 mg in repeated doses. The cure rate of mebendazole in the treatment of Ascaris infection was remarkably high and satisfactory in every dose groups. The egg reduction rates were all over 98 percent in every dose groups. Side effects were observed during the treatment, mainly mild and transient gastrointestinal troubles, and not exacerbated by the increase of doses upto 300 mg in single dose. Above results confirmed that in case of mass chemotherapy of Ascaris infection, 100 mg or 200 mg of single dose treatment is sufficient to achieve the economic and acceptable method of treatment.

Online source: www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=12902780&dopt=Abstract mebendazole Vermox



Vermox
Anthelmintic Efficacy Of Methyl-5-Benzoylbenzimidazole-2-Carbamate(Mebendazole) Against Multiple Helminthic Infections.

Seo BS, Cho SY, Kang SY, Chai JY.

Department of Parasitology and Institute of Endemic Diseases, College of Medicine, Seoul National University, Korea.

A clinical trial of Korean Patent mebendazole was undertaken upon some intestinal helminthic infections in 288 rural Koreans residing in Pochun and Jinyang Gun, from November to December, 1976. They were examined by the cellophane thick smear technique, Stoll's egg counting technique and/or Scotch-tape anal swab before and 3 weeks after the treatment. The administered dose of mebendazole was 600 mg, divided by 100 mg, twice daily for 3 consecutive days disregarding the body weight and the age of the cases. It was confirmed that mebendazole is very effective, broad-spectrum anthelmintic, especially against Ascaris, Ancylostoma, Trichostrongylus and Enterobius infections. Their negative conversion rate and egg reduction rate were respectively; 94.0 and 99.6 per cent in Ascaris, 71.4 and 97.3 per cent in Ancylostoma and 95.0 and 100 per cent in Trichostrongylus. The negative conversion rate in Enterobius was 92.3 per cent. The anthelmintic efficacy against T. trichiura infection was not satisfactory in spite of low worm burden (negative conversion rate, 27.3%, egg reduction rate, 65.5%).

Online source: www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=12913430&dopt=Abstract mebendazole Vermox