SUMMARY. A commercially available substrate-labelled fluorescent immunoassay procedure has been modified to create a simple rapid method for the determination of capillary phenytoin concentration in dried filter paper blood spots of patients on phenytoin therapy. The specimens are collected and despatched to the laboratory by the patient, thus domiciliary monitoring of phenytoin therapy can take place. The technique was validated by comparing the phenytoin results of simultaneously collected capillary dried blood spots and conventional plasma samples. The technique offers a convenient method for overcoming many of the practical problems of monitoring phenytoin therapy in epilepsy.
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GamlenTRJamesHCBatstoneGF. The determinations of blood spot glucose concentration using a rapid kinetic assay. Scand J Clin Lab Invest1982; 42: 643–5.
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AlbaniMOldigsH-DToselandPA. Kapillar-blutmethode zur bestimmung antikonvulsiver substanzen ant einsendebasis. Monatsschr Kinderheilkd1980; 128: 371–4.
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WongRCBurdJFCarricoRJ, Substrate-labelled fluorescent immunoassay for phenytoin in human serum. Clin Chem.1979; 25: 686–91.
Delgado-EscuetaAVTreimanDMWalshGO. The treatable epilepsies. N Engl J Med.1983; 308: 1576–84.
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JonesAL. Medical audit of the care of patients with epilepsy in one group practice. J R Coll Gen Pract1980; 30: 396–400.
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CoombesEJGamlenTRBatstoneGF, The validation of a fluoroimmunoassay for the determination of theophylline concentration in dried blood spots suitable for therapeutic drug monitoring. Clin Chim Acta1984; 136: 187–95.
BorondyPDillWAChangT, Effect of protein binding on the distribution of 5,5-diphenylhydantoin between plasma and red cells. Ann NY Acad Sci.1973; 226: 82–7.
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SherwinALHarveyCDLeppikIE, Correlation between red cell and free plasma phenytoin levels in renal disease. Neurology1976; 26: 874–8.
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GamlenTRJamesHCBatstoneGF. The determinations of blood spot glucose concentration using a rapid kinetic assay. Scand J Clin Lab Invest1982; 42: 643–5.
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AlbaniMOldigsH-DToselandPA. Kapillar-blutmethode zur bestimmung antikonvulsiver substanzen ant einsendebasis. Monatsschr Kinderheilkd1980; 128: 371–4.
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WongRCBurdJFCarricoRJ, Substrate-labelled fluorescent immunoassay for phenytoin in human serum. Clin Chem.1979; 25: 686–91.
Delgado-EscuetaAVTreimanDMWalshGO. The treatable epilepsies. N Engl J Med.1983; 308: 1576–84.
26.
JonesAL. Medical audit of the care of patients with epilepsy in one group practice. J R Coll Gen Pract1980; 30: 396–400.
27.
CoombesEJGamlenTRBatstoneGF, The validation of a fluoroimmunoassay for the determination of theophylline concentration in dried blood spots suitable for therapeutic drug monitoring. Clin Chim Acta1984; 136: 187–95.
BorondyPDillWAChangT, Effect of protein binding on the distribution of 5,5-diphenylhydantoin between plasma and red cells. Ann NY Acad Sci.1973; 226: 82–7.
30.
SherwinALHarveyCDLeppikIE, Correlation between red cell and free plasma phenytoin levels in renal disease. Neurology1976; 26: 874–8.
31.
GamlenTRJamesHCBatstoneGF. The determinations of blood spot glucose concentration using a rapid kinetic assay. Scand J Clin Lab Invest1982; 42: 643–5.
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AlbaniMOldigsH-DToselandPA. Kapillar-blutmethode zur bestimmung antikonvulsiver substanzen ant einsendebasis. Monatsschr Kinderheilkd1980; 128: 371–4.
33.
WongRCBurdJFCarricoRJ, Substrate-labelled fluorescent immunoassay for phenytoin in human serum. Clin Chem.1979; 25: 686–91.
Delgado-EscuetaAVTreimanDMWalshGO. The treatable epilepsies. N Engl J Med.1983; 308: 1576–84.
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JonesAL. Medical audit of the care of patients with epilepsy in one group practice. J R Coll Gen Pract1980; 30: 396–400.
37.
CoombesEJGamlenTRBatstoneGF, The validation of a fluoroimmunoassay for the determination of theophylline concentration in dried blood spots suitable for therapeutic drug monitoring. Clin Chim Acta1984; 136: 187–95.
BorondyPDillWAChangT, Effect of protein binding on the distribution of 5,5-diphenylhydantoin between plasma and red cells. Ann NY Acad Sci.1973; 226: 82–7.
40.
SherwinALHarveyCDLeppikIE, Correlation between red cell and free plasma phenytoin levels in renal disease. Neurology1976; 26: 874–8.
