This study was conducted to determine the effect of oxantel/pyrantel tablets, oxantel suspension, pyrantel dry syrup and pyrantel tablets against T. trichiurus and A. lumbricoides infections. Twenty-four cases of mixed infections of T. trichiurus and A. lumbricoides were treated with oxantel/pyrantel tablets at a single dose of 20 mg/kg of body weight, and 49 cases of single infection of T. trichiurus were administered oxantel suspension at a single dose of 15 mg/kg of body weight. On the other hand, single infection of A. lumbricoides in 18 cases was administered pyrantel dry syrup at a single dose of 5 mg/kg of body weight. In the above 91 cases, the negative conversion rate and the egg reduction rate of egg out-put before and after the drug administration were examined by the cellophane thick smear method and Stoll's egg counting technique. A follow-up examination was carried out 3-4 weeks after the drug administration. Other 59 cases of single and mixed infection of T. trichiurus and A. lumbricoides were examined by the cellophane thick smear method only and administered pyrantel tablets at a single dose of 2.5 mg/kg of body weight. The results were summarized as follows: The prevalence rates of T. trichiurus and A. lumbricoides infection in this study were 42.8% and 27.2% respectively by the cellophane thick smear method among 1,066 stool specimens. The egg negative conversion rate and the egg reduction rate in the administration of oxantel/pyrantel tablets at a single dose of 20 mg/kg body weight were 75.0% and 97.8% respectively in T. trichiurus infection and 100% each in A. lumbricoides. The egg negative conversion rate and the egg reduction rate in the administration of oxantel suspension at a single dose of 15 mg/kg body weight were 85.7% and 93.0% respectively in sinlge infection of T. trichiurus. The egg negative conversion rate and the egg reduction rate in the administration of pyrantel dry syrup at a single dose of 5 mg/kg body weight were 100% each in single infection of A. lumbricoides. The qualitative evaluation in cases of single and mixed infection of T. trichiurus and A. lumbricoides were by means of pyrantel tablets at a single dose of 2.5 mg/kg body weight, the cure being 100% against A. lumbricoides but 17.0% against T. trichiurus. There were no undesirable side effects in this study and oxantel suspension and pyrantel dry syrup were well accepted and tolerated.
