Toxicokinetics of paraquat in Korean patients with acute poisoning.
10.4196/kjpp.2016.20.1.35
- Author:
Hak Jae KIM
1
;
Hyung Ki KIM
;
Hwayoung LEE
;
Jun Seok BAE
;
Jun Tack KOWN
;
Hyo Wook GIL
;
Sae Yong HONG
Author Information
1. Department of Clinical Pharmacology, Soonchunhyang University College of Medicine, Cheonan 31151, Korea.
- Publication Type:Original Article
- Keywords:
Paraquat;
Poisoning;
Toxicokinetics
- MeSH:
Dithionite;
Eating;
Emergency Service, Hospital;
Half-Life;
Humans;
Paraquat*;
Pharmacokinetics*;
Plasma;
Poisoning*;
Suicide
- From:The Korean Journal of Physiology and Pharmacology
2016;20(1):35-39
- CountryRepublic of Korea
- Language:English
-
Abstract:
To conduct a kinetic study of paraquat (PQ), we investigated 9 patients with acute PQ intoxication. All of them ingested more than 20 ml of undiluted PQ herbicide to commit suicide and arrived at our hospital early, not later than 7 h after PQ ingestion. The urine dithionite test for PQ in all of the nine patients was strongly positive at emergency room. Blood samples were obtained every 30 min for the first 2~3 h and then every 1 or 2 h, as long as the clinical progression was stable among the patients for 30 h after PQ ingestion. The area under the plasma concentration-time curve (AUCinf), which was extrapolated to infinity, was calculated using the trapezoidal rule. Toxicokinetic parameters, such as the terminal elimination half-life, apparent oral clearance, and apparent volume of distribution (Vd/F) were calculated. The maximum PQ concentration (Cmax) and the time to reach maximum PQ concentration (Tmax) were also obtained. Plasma PQ concentrations in nine patients were well described by a bi-exponential curve with a mean terminal elimination half-life of 13.1+/-6.8 h. Cmax and AUCinf were 20.8+/-25.7 mg/l and 172.5+/-160.3 h.mg/l, respectively. Apparent volume of distribution and apparent oral clearance were 50.9+/-61.3 l/kg and 173.4+/-111.2 l/h, respectively. There were a significant correlation (r =0.84; p<0.05) between the PQ amount ingested and Cmax. AUCinf also showed a significant correlation (r =0.83; p<0.05) with the PQ amount ingested. These correlations provide evidence that PQ has dose-linear toxicokinetic characteristics.
