caa a22 4500 397591047 CHVBK 20180308164938.0 cr unu---uuuuu 161202e199607 xx s 000 0 eng 10.1093/jac/38.1.75 doi (NATIONALLICENCE)oxford-10.1093/jac/38.1.75 Anti-toxoplasma effect of pyrimethamine, trimethoprim and sulphonamides alone and in combination: implications for therapy [Elektronische Daten] [André J. A. M. van der Ven, Esther M. E. Schoondermark-van de Ven, Wil Camps, Willem J. G. Melchers, Peter P. Koopmans, Jos W. M. van der Meer, Joep M. D. Galama] The aim of the present study was to determine the in-vitro susceptibility of Toxoplasma gondii to dihydrofolate rcductase inhibitors and sulphonamides alone, and in combination. It was found that pyrimethamine had the most potent anti-Toxoplasma activity, while sulphadiazine, sulphamethoxazole and sul-phametrole were approximately equally effective, but only at a high concentration. The 50% inhibitory concentration of sulphamethoxazole was determined using different fixed concentrations of pyrimethamine or trimethoprim. It was found that a ten-fold increment of the concentration of pyrimethamine, reduced the IC50 of sulphamethoxazole 1000 times. The influence of trimethoprim on the IC50 of sulphamethoxazole was less concentration dependent. Addition of dihydrofolate or tetrahydrofolate did not influence the IC50 of pyrimethamine. In conclusion, the present dose recommendations for sulphonamides, when combined with pyrimethamine, may be unnecessarily high. There may be a justification for dose reduction of sulphonamides in order to prevent side effects. © 1996 by the British Society for Antimicrobial Chemotherapy Original articles nationallicence van der Ven André J. A. M. Departments of General Internal Medicine P.O. Box 9101, 6500 HB Nijmegen, The Netherlands aut Schoondermark-van de Ven Esther M. E. Medical Microbiology, University Hospital Nijmegen P.O. Box 9101, 6500 HB Nijmegen, The Netherlands aut Camps Wil Medical Microbiology, University Hospital Nijmegen P.O. Box 9101, 6500 HB Nijmegen, The Netherlands aut Melchers Willem J. G. Medical Microbiology, University Hospital Nijmegen P.O. Box 9101, 6500 HB Nijmegen, The Netherlands aut Koopmans Peter P. Departments of General Internal Medicine P.O. Box 9101, 6500 HB Nijmegen, The Netherlands aut van der Meer Jos W. M. Departments of General Internal Medicine P.O. Box 9101, 6500 HB Nijmegen, The Netherlands aut Galama Joep M. D. Departments of General Internal Medicine, P.O. Box 9101, 6500 HB Nijmegen, The Netherlands, P.O. Box 9101, 6500 HB Nijmegen, The Netherlands aut Journal of Antimicrobial Chemotherapy Oxford University Press 38/1(1996-07), 75-80 0305-7453 38:1<75 1996 38 jac https://doi.org/10.1093/jac/38.1.75 text/html Onlinezugriff via DOI 1 other jats NATIONALLICENCE 856 40 https://doi.org/10.1093/jac/38.1.75 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- van der Ven André J. A. M. Departments of General Internal Medicine P.O. Box 9101, 6500 HB Nijmegen, The Netherlands aut NATIONALLICENCE 700 1- Schoondermark-van de Ven Esther M. E. Medical Microbiology, University Hospital Nijmegen P.O. Box 9101, 6500 HB Nijmegen, The Netherlands aut NATIONALLICENCE 700 1- Camps Wil Medical Microbiology, University Hospital Nijmegen P.O. Box 9101, 6500 HB Nijmegen, The Netherlands aut NATIONALLICENCE 700 1- Melchers Willem J. G. Medical Microbiology, University Hospital Nijmegen P.O. Box 9101, 6500 HB Nijmegen, The Netherlands aut NATIONALLICENCE 700 1- Koopmans Peter P. Departments of General Internal Medicine P.O. Box 9101, 6500 HB Nijmegen, The Netherlands aut NATIONALLICENCE 700 1- van der Meer Jos W. M. Departments of General Internal Medicine P.O. Box 9101, 6500 HB Nijmegen, The Netherlands aut NATIONALLICENCE 700 1- Galama Joep M. D. Departments of General Internal Medicine, P.O. Box 9101, 6500 HB Nijmegen, The Netherlands, P.O. Box 9101, 6500 HB Nijmegen, The Netherlands aut NATIONALLICENCE 773 0- Journal of Antimicrobial Chemotherapy Oxford University Press 38/1(1996-07), 75-80 0305-7453 38:1<75 1996 38 jac Metadata rights reserved CC BY-NC-4.0 http://creativecommons.org/licenses/by-nc/4.0 nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-oxford