抗発作薬を服用している患者におけるフェロディピン生物学的利用性の低下
S Capewell1, S Freestone, J A Critchley
1Department of Clinical Pharmacology, Royal Infirmary, Edinburgh.
Lancet (London, England)
|August 27, 1988
まとめ
抗震性療法を受けている患者は,フェロディピン生物学的利用性が著しく低下しています. 治療用血濃度を達成するために,酵素誘導抗薬治療を受けている個人にフェロディピンより高い用量が必要である.
科学分野:
- 薬理学 薬理学とは
- クリニック薬局 臨床薬局
背景:
- フェロディピン (Felodipine) は,広範囲にわたるファーストパス肝臓代謝を有する二酸化ピリジンカルシウム対抗剤です.
- フェロディピンの正常な経口生物利用率は約15%です.
研究 の 目的:
- 慢性抗発作療法によるマイクロソーマル酵素誘導の患者におけるフェロディピンの配分を調査する.
- 誘導された患者と正常なボランティアにおけるフェロディピンの血濃度と生物学的利用性を比較する.
主な方法:
- フェロディピンの単発口投与量5mgは,抗震性療法を受けている10人の患者と,年齢と性別が一致した12人の健康なボランティアに投与されました.
- 血フェロディピン濃度は,ピーク濃度と曲線下の面積 (AUC) を決定するために測定されました.
主要な成果:
- 発作患者は,正常なボランティアと比較して,プラズマフェロディピン濃度が著しく低下した.
- 患者の平均ピーク濃度は1.6nmol/lで,対照群では8.9nmol/lでした.
- 患者の平均AUCは2.0nmol.h/lであり,対照群では30.0nmol.h/lであり,相対生物利用率は6.6%のみであった.
結論:
- 慢性抗薬療法は,フェロディピンの経口生物利用性を著しく低下させる.
- 酵素誘発性抗発作薬を服用している患者は,治療的なレベルに到達するために,フェロディピンの大量投与を必要とします.
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