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Optimized Griess Reaction for UV-Vis and Naked-eye Determination of Anti-malarial Primaquine
Published on: October 11, 2019
Urinary elimination kinetics of pyrimethamine
J B Mouankie1, W Senczuk, E Florek
1Faculty of Pharmacy, Poznan University of Medical Sciences, Poznan, Poland.
European Journal of Drug Metabolism and Pharmacokinetics
|February 20, 2010
Summary
This study investigated pyrimethamine urine elimination kinetics in healthy males. Approximately 13.4% of the pyrimethamine dose was excreted unchanged, suggesting a two-compartmental elimination model for this antimalarial drug.
Area of Science:
- Pharmacokinetics
- Drug Metabolism
- Clinical Pharmacology
Background:
- Pyrimethamine is an essential antimalarial drug.
- Understanding its elimination is crucial for effective dosing and toxicity management.
- Previous studies have not fully elucidated its urinary excretion kinetics.
Purpose of the Study:
- To investigate the kinetics of pyrimethamine elimination in urine.
- To determine the percentage of unchanged pyrimethamine excreted in urine.
- To model the drug's elimination process and propose quantitative exposure tests.
Main Methods:
- Single oral dose administration of pyrimethamine (50, 75, 100 mg) to six healthy male volunteers.
- Urine sample collection and analysis using a modified Bonini et al. and Garber et al. method.
- Application of an open kinetic two-compartmental model to describe elimination.
Main Results:
- Approximately 13.4% (± 1.3%) of the administered pyrimethamine dose was eliminated in unchanged form via urine.
- The elimination process was successfully modeled using an open kinetic two-compartmental model.
- A formula describing pyrimethamine elimination over time was derived.
Conclusions:
- Pyrimethamine undergoes significant metabolism before urinary excretion.
- The established two-compartmental model provides a framework for understanding pyrimethamine pharmacokinetics.
- Proposed quantitative exposure tests can aid in assessing drug absorption and potential toxicity.
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