Population pharmacokinetic and pharmacodynamic properties of intramuscular quinine in Tanzanian children with severe Falciparum malaria.

Abstract

Although artesunate is clearly superior, parenteral quinine is still used widely for the treatment of severe malaria. A loading-dose regimen has been recommended for 30 years but is still often not used. A population pharmacokinetic study was conducted with 75 Tanzanian children aged 4 months to 8 years with severe malaria who received quinine intramuscularly; 69 patients received a loading dose of 20 mg quinine dihydrochloride (salt)/kg of body weight. Twenty-one patients had plasma quinine concentrations detectable at baseline. A zero-order absorption model with one-compartment disposition pharmacokinetics described the data adequately. Body weight was the only significant covariate and was implemented as an allometric function on clearance and volume parameters. Population pharmacokinetic parameter estimates (and percent relative standard errors [%RSE]) of elimination clearance, central volume of distribution, and duration of zero-order absorption were 0.977 liters/h (6.50%), 16.7 liters (6.39%), and 1.42 h (21.5%), respectively, for a typical patient weighing 11 kg. Quinine exposure was reduced at lower body weights after standard weight-based dosing; there was 18% less exposure over 24 h in patients weighing 5 kg than in those weighing 25 kg. Maximum plasma concentrations after the loading dose were unaffected by body weight. There was no evidence of dose-related drug toxicity with the loading dosing regimen. Intramuscular quinine is rapidly and reliably absorbed in children with severe falciparum malaria. Based on these pharmacokinetic data, a loading dose of 20 mg salt/kg is recommended, provided that no loading dose was administered within 24 h and no routine dose was administered within 12 h of admission. (This study has been registered with Current Controlled Trials under registration number ISRCTN 50258054.).

• Authors: Ilse C E Hendriksen, Deogratius Maiga, Martha M Lemnge, George Mtove, Samwel Gesase, Hugh Reyburn, Niklas Lindegardh, Nicholas P J Day, Lorenz von Seidlein, Arjen M Dondorp, Joel Tarning, Nicholas J White
• Journal: Antimicrobial agents and chemotherapy (Antimicrob Agents Chemother) Vol. 57 Issue 2 Pg. 775-83 (Feb 2013) ISSN: 1098-6596 [Electronic] United States
• PMID: 23183442 (Publication Type: Controlled Clinical Trial, Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• Antimalarials
• Quinine

Topics

• Antimalarials (administration & dosage, adverse effects, pharmacokinetics, therapeutic use)
• Child
• Child, Preschool
• Humans
• Infant
• Injections, Intramuscular
• Malaria, Falciparum (drug therapy)
• Plasmodium falciparum (drug effects)
• Quinine (administration & dosage, adverse effects, pharmacokinetics, therapeutic use)
• Tanzania