Pyrantel embonate in treatment of hookworm infestation.

The efficacy of pyrantel embonate (1,4,5,6-tetrahydro-1-methyl-2-(trans-2-(2-thienyl)-vinyl)-pyrimidine embonic acid salt; Combantrin) was evaluated in 60 cases of hookworm infestation. They were divided into six groups of 10 cases. Pyrantel embonate was administered orally, in dosage schedules (randomized) of 100, 75, 50, 20, 15, and 10 mg/kg of body weight. The stool examination for hookworm ova and coproculture were positive in each case. The predominant species was Ancylostoma duodenale (in 58 patients). After treatment with pyrantel embonate the stool examination for hookworm ova and coproculture were negative on the 10th and 15th days in each group. The blood levels of the drug were significantly higher in patients receiving 100 and 75 mg/kg body weight. In groups A and B one patient experienced nausea and vomiting on the day of administration of drug. There were no abnormal changes in liver function tests or blood urea levels in any of the groups. Hence the optimum single dose of the drug effective against hookworm infestation is 10 mg/kg body weight, and further studies are required to evaluate the minimum effective dose of pyrantel embonate.