title: Impact of drug dosage and brand on bioavailability and efficacy of praziquantel.
abstract: The efficacy of two brands (brand 1 = Biltricide; Bayer AG, Leverkusen, Germany; brand 2 = Distocide; EPICO pharmaceuticals, Cairo, Egypt) of praziquantel (PZQ) in full and half doses (40 and 20 mg kg-1) monitored as percentage egg reduction and cure rate was investigated in S. mansoni infected school-children. A total of 506 school-children (8-16 years of age) were classified into three groups according to their intensity of infection, heavy [> 500 eggs per grams (epg)], moderate (100-500 epg) and light (< 100 epg), after examination three stool samples (three slides per sample) on three consecutive days. Percentage egg reduction and cure rate were monitored 4 and 10 weeks post-treatment for each dose regimen in the different test groups. Before testing the efficacy of either bran in patients, the pharmacokinetic parameters of the two brands were studied in non-infected normal volunteers. Statistical analysis of the pharmacokinetic parameters of brand 1 vs brand 2 (in a dose of 20 or 40 mg kg-1) revealed no significant difference in elimination (ke), absorption rate constant (ka), elimination half life (t1/2e), area under the time-concentration curve (Auc), serum maximum concentration (Cpmax) and time to maximum concentration (Tmax). As regards the efficacy of test drugs, statistical analysis revealed that up to 10 weeks post-treatment the two brands of PZQ in full dose were equally effective in reducing egg count as their half doses except in heavily infected cases treated with brand 2 of PZQ.(ABSTRACT TRUNCATED AT 250 WORDS)
authors.affiliation: Department of Pharmacology and Tropical Medicine, Theodor Bilharz Research Institute, Imbaba, Giza, Egypt.
authors.forename: A
authors.initials: A
authors.lastname: Metwally
authors.forename: J
authors.initials: J
authors.lastname: Bennett
authors.forename: S
authors.initials: S
authors.lastname: Botros
authors.forename: F
authors.initials: F
authors.lastname: Ebeid
authors.forename: G el D
authors.initials: Gel D
authors.lastname: el attar
mesh_terms: D000293:Adolescent; D000328:Adult; D000818:Animals; D001682:Biological Availability; D002648:Child; D004305:Dose-Response Relationship, Drug; D004334:Drug Administration Schedule; D005243:Feces / Q000469:parasitology; D006801:Humans; D008297:Male; D010270:Parasite Egg Count; D011223:Praziquantel / Q000493:pharmacokinetics* / Q000494:pharmacology / Q000627:therapeutic use*; D012550:Schistosoma mansoni / Q000187:drug effects; D012555:Schistosomiasis mansoni / Q000188:drug therapy / Q000469:parasitology; D013997:Time Factors
chemical_list: D011223:Praziquantel