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Optimized Griess Reaction for UV-Vis and Naked-eye Determination of Anti-malarial Primaquine
Published on: October 11, 2019
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Pharmacokinetic interactions between primaquine and chloroquine
Sasithon Pukrittayakamee1, Joel Tarning2, Podjanee Jittamala1
1Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand.
Antimicrobial Agents and Chemotherapy
|April 2, 2014
Summary
Combining chloroquine and primaquine for malaria treatment increases primaquine levels in the blood. This interaction may enhance the drugs
Area of Science:
- Pharmacology
- Infectious Diseases
- Clinical Trials
Background:
- Chloroquine and primaquine are standard treatments for Plasmodium vivax and ovale malaria.
- Over 50 years of use established this regimen.
- Understanding drug interactions is crucial for optimizing malaria therapy.
Purpose of the Study:
- To investigate the pharmacokinetic interaction between chloroquine and primaquine.
- To assess the impact of coadministration on drug concentrations and safety.
- To explore potential mechanisms for observed therapeutic synergy.
Main Methods:
- Open-label, crossover pharmacokinetic study.
- 16 healthy volunteers received single oral doses of primaquine, chloroquine, or both.
- Plasma drug concentrations and electrocardiograms were monitored.
Main Results:
- Coadministration significantly increased plasma concentrations of primaquine and its metabolite carboxyprimaquine.
- Chloroquine and desethylchloroquine pharmacokinetics were unaffected.
- Slight QTc interval prolongation occurred with chloroquine, not exacerbated by primaquine.
Conclusions:
- The pharmacokinetic interaction between chloroquine and primaquine may explain synergistic effects against malaria relapse.
- This study provides evidence supporting the combined use of these antimalarials.
- Further research can optimize dosing strategies for radical curative regimens.
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