pyrantel and flubendazole

A series of randomized, controlled, masked, field (veterinary patient) studies were conducted in the USA and Europe to evaluate the efficacy of selamectin, a novel macrocyclic lactone of the avermectin subclass, in the treatment of naturally acquired gastrointestinal nematode infections in cats. After confirmation of ascarid and/or hookworm infection, 298 cats of various ages and breeds were randomly assigned to treatment with selamectin (n=202) or an existing commercially approved positive-control product (n=96). Unit doses of selamectin (providing a minimum dosage of 6mgkg(-1)) were administered topically to the skin in a single spot at monthly intervals. Quantitative fecal examinations were performed on days 0 (before treatment), 30, and 60. In the selamectin-treated cats, fecal ascarid egg counts were reduced by 99.6 to 100% on day 30, and by 99.9 to 100% on day 60. Fecal hookworm egg counts were reduced by 98.3% on day 30, and by 100% on day 60 in the selamectin-treated cats. The positive-control products achieved reductions in egg counts of 96.5 to 100% (ascarids) and 98.9 to 99.9% (hookworms). These studies have shown that monthly topical administration of selamectin is safe and highly effective in the treatment of naturally acquired ascarid and hookworm infections in cats.

Topics: Ancylostomatoidea; Animals; Anthelmintics; Cat Diseases; Cats; Ivermectin; Mebendazole; Nematode Infections; Parasite Egg Count; Praziquantel; Pyrantel

Fourteen of 23 dogs developing patent Trichuris vulpis infections by 120 days p.i. with 5000 embryonated eggs were allocated into three groups. One group was treated with flubendazole 220 mg chewable tablets (Flubenol) at the recommended dose regimen once daily for 3 days. The second group was given the recommended single treatment with a tablet containing 150 mg febantel, 144 mg pyrantel embonate and 50 mg praziquantel in combination (Drontal Plus). The third group remained untreated. All dogs were necropsied for worm counts 10 or 11 days after (first) treatment. No worms were recovered from the flubendazole treated dogs resulting in a significant worm count reduction of 100%. In contrast, 2 of 5 animals treated with the combination of febantel, pyrantel embonate and praziquantel remained infected; the geometric mean worm burden was reduced by 99.4% as compared to the control group but did not differ significantly from those of the controls.

Topics: Animals; Antinematodal Agents; Dog Diseases; Dogs; Drug Therapy, Combination; Female; Guanidines; Male; Mebendazole; Praziquantel; Pyrantel; Tablets; Treatment Outcome; Trichuriasis; Trichuris

Information about genetic changes during the selection process could indicate mechanisms underlying the spread of resistance to anthelmintic drugs. For clarification of the role of the Mpi locus encoding mannose-phosphate isomerase enzyme in determining resistance, genotyping of Oesophagostomum dentatum strains was performed using an isoelectrofocusing technique. In levamisole- and pyrantel-selected strains the allele associated with resistance has probably been found. Significant values for genetic differentiation between treated and untreated strains of common origin were recorded by F(st) indices (theta = 0.078; P = 0.0008). The specific genomic makeup of a flubendazole-resistant strain, which did not correlate with that of the remaining isolates, might be ascribed to a different action of the anthelmintic or different environmental conditions under which resistance against this drug arose. The absence of heterozygotes in male populations indicated an XX/X0 system of sex determination for the Mpi locus, thus providing a greater potential for the development of resistance. A possible involvement of alleles linked with mannose-phosphate isomerase in alterations of membrane receptors that can be associated with resistance against imidothiazole-based drugs is discussed.

Topics: Animals; Anthelmintics; Drug Resistance; Female; Genetic Linkage; Levamisole; Male; Mebendazole; Oesophagostomum; Pyrantel; Sex Chromosomes; Swine; Thiazoles

The results of four alternative methods of mean faecal egg count reduction percentage (FECR%) calculations were evaluated and compared using data obtained for Oesophagostomum spp. from ten sow herds. The estimates of FECR% and 95% confidence limits obtained using the four methods were different. However, there were few discrepancies in the final decision as to whether a given herd carried drug resistant isolates or not. The methods that used geometric means were more appropriate than those that used the arithmetic mean as the measure of central tendency for eggs per gram of faeces (EPG) values. The use of geometric mean EPG values in calculations has been criticized from several viewpoints, one of which is that its use reduces the comparability of reports between laboratories. If the geometric mean is to be used as we suggest in FECR% calculations, the appropriate references, number of animals in each group, minimum and maximum EPG values and the factor added to zero EPG counts should be reported in order to improve the comparability. The difficulty in obtaining groups with similar pre-treatment EPG values in field situations suggested the inclusion of pre-treatment EPG values in the calculations as an adjustment procedure. The importance of including a non-treated control group in calculations was demonstrated during this study. Therefore, we suggest the use of geometric mean EPG values, to include pre-treatment EPG values and to include the egg counts from the control group in FECR% calculations. The interpretation of the resulting FECR estimate may be different according to the purpose for which the testing procedure is carried out, e.g. survey in detecting anthelmintic resistance, control field tests, etc.

Topics: Animals; Anthelmintics; Confidence Intervals; Drug Resistance; Feces; Female; Ivermectin; Levamisole; Mebendazole; Models, Statistical; Oesophagostomiasis; Oesophagostomum; Parasite Egg Count; Piperazine; Piperazines; Pyrantel; Swine; Swine Diseases

Clinical trials on the three broad spectrum anthelmintics against trichuriasis, ascariasis and hookworm infection were carried out in a rural community in Irosin, Sorsogon. Flubendazole (Fluvermal) appears to be a promising drug against trichuriasis particularly when periodic mass treatment of a community is carried out. Mebendazole (Antiox) also appears to be promising given as single dose during mass treatment of soil-transmitted helminthiasis. As shown in previous studies, oxantel-pyrantel (Quantrel) should be given at 15 mg/kg body weight at 12-hour intervals or 20 mg/kg body weight single dose rather than 10 mg/kg body weight in a single dose when treating trichuriasis.

Topics: Anthelmintics; Dose-Response Relationship, Drug; Drug Combinations; Drug Evaluation; Feces; Humans; Mebendazole; Philippines; Pyrantel; Soil; Trichuriasis