版权说明:本文档由用户提供并上传,收益归属内容提供方,若内容存在侵权,请进行举报或认领
文档简介
1、Pharmacokinetics(how the body handles drugs) (a,d,m,e)Drugs cross membranes by passive diffusion or active transportThe vast majority of drugs gain access to their site of action by passive diffusionmost drugs are weak acids or bases:when H increases get more HA and BH+only the non-ionized form can
2、cross cell membranesHA H+ + A-BH+ B + H+ absorption of drugsoral absorption is more complex:tablet-dissolves in gut water-lipid soluble form crosses gut barrier-must escape liver (first pass metabolism)amount absorbed is bioavailabilitydistribution of drugsonce in the body, drugs distribute to tissu
3、esVolume of distribution (Vd) is a calculation of the apparent volume in which a drug is dissolvedVd = Dose (mg)/Cp0 (mg/L)= Litres sometimes the Vd is anatomically “correct” sometimes its notdrugs with low Vd are often bound to plasma proteinsdrugs with high Vd are often bound to tissue components
4、(proteins or fat)metabolism The purpose of drug metabolism is to render drugs water soluble, so they can be excreted by the kidney The liver is the main organ of metabolism and often inactivates drugs on their way from the GI tract to the body.This is called the first-pass effect filtration: free dr
5、ug only, not protein bound reabsorption:passive, lipid soluble form only (pH) secretion:active, acids and bases, saturableif the drug is water soluble, the kidney can excrete it.excretionRate processesfirst-order constant fraction or percent of drug eliminated per unit of timeMost drug disappear fro
6、m plasm by this processThe half life is constantRate processeszero-order constant amount of drug eliminated per unit of timeThe half life is not constant, but depends on the concentrationTime to steady state or elimination is independent of dosage, but depends only on the half lifeRequires 5 elimination half-lives to reach 97% of steady stat
温馨提示
- 1. 本站所有资源如无特殊说明,都需要本地电脑安装OFFICE2007和PDF阅读器。图纸软件为CAD,CAXA,PROE,UG,SolidWorks等.压缩文件请下载最新的WinRAR软件解压。
- 2. 本站的文档不包含任何第三方提供的附件图纸等,如果需要附件,请联系上传者。文件的所有权益归上传用户所有。
- 3. 本站RAR压缩包中若带图纸,网页内容里面会有图纸预览,若没有图纸预览就没有图纸。
- 4. 未经权益所有人同意不得将文件中的内容挪作商业或盈利用途。
- 5. 人人文库网仅提供信息存储空间,仅对用户上传内容的表现方式做保护处理,对用户上传分享的文档内容本身不做任何修改或编辑,并不能对任何下载内容负责。
- 6. 下载文件中如有侵权或不适当内容,请与我们联系,我们立即纠正。
- 7. 本站不保证下载资源的准确性、安全性和完整性, 同时也不承担用户因使用这些下载资源对自己和他人造成任何形式的伤害或损失。
最新文档
- 2024年河北中考道德与法治一轮复习-国情教育板块-课时7 中国人 中国梦(九上第八课)
- G1工业锅炉司炉模拟考试题库试卷二
- 年新增90000万平方米高安全性锂离子电池用新型涂覆隔扩建项目环境影响报告表
- 年产200万个包装制品加工环评
- 年产 6000 套木质家具生产线项目环境影响报告
- 南阳医专三年制专科临床医学专业人才培养方案
- 模板早拆施工技术规程
- 食品安全大数据项目可行性分析报告
- 新型全液压钻机项目建议书
- 简约国际禁毒日节日宣传
- 2023年河北省高考物理真题试卷及答案
- 《湖南省医疗保险“双通道”管理药品使用申请表》
- 配电箱每日检查记录表;
- 小学数学四年级上册奥数题及答案100道
- 幼升小个人简历模板
- 刑释解教人员安置帮教工作管理办法
- 最大团问题-回溯法.ppt
- 妊娠合并心脏病的诊治专家共识(2016)
- 《设计班徽》PPT课件.ppt
- 风温肺热病(重症社区获得性肺炎)中医临床路径2018版
- JJG 577-2012 膜式燃气表检定规程
评论
0/150
提交评论