Pharmacokinetics and pharmacodynamics of drugs of abuse

有许多因素影响着 对毒品上瘾。给药途径是主要的 决定药物进入体内的速度， 中枢神经系统中的受体， 方面的影响.临床研究正在进行中， 不同给药途径的重要性以及 药物和活性代谢物的血液浓度， 伴随药物作用。对海洛因、可卡因和大麻的研究 通过静脉内、烟熏、鼻内（海洛因和 可卡因）和口服途径正在进行或已经进行。 新的举措包括评估 长期使用可卡因和可卡因戒断。并发 收集生理、行为和性能指标 沿着血液样本。分析血液样本中的药物 固相萃取-气相色谱/质谱法 光谱法静脉注射和烟熏途径产生快速的 药理学作用的发生以及早期出现 血液中的药物和代谢物。很明显，吸烟路线 使个体能够获得类似的药理作用， 通过静脉给药产生，但没有 使用针头造成的创伤。瞳孔直径等生理指标 与药物和代谢物的血液水平进行比较。的证据 在以下情况下观察到分布到效应部位的延迟 吸食大麻，但海洛因和可卡因后的药物作用 给药与并发血液更接近 浓度的起效时间延迟较长， 鼻内给药，口服后变得明显 局

There are many factors which influence the addictiveness of a drug. The route of administration is a major determinant of the speed of drug entry into the body and to receptors in the central nervous system which produce resultant effects. Clinical studies are in progress which determine the importance of different routes of administration and the relationship of blood concentrations of drug and active metabolites to concomitant drug effects. Studies of heroin, cocaine and marijuana administration by the intravenous, smoked, intranasal (heroin and cocaine) and oral routes are underway or have been performed. New initiatives include an evaluation of the consequences of chronic cocaine use and cocaine withdrawal. Concurrent physiological, behavioral and performance measures are collected along with blood specimens. Blood specimens are analyzed for drug and metabolites by solid phase extraction-gas chromatography/mass spectrometry. The intravenous and smoked routes produce a rapid onset of pharmacologic effects together with an early appearance of drug and metabolites in blood. It is evident that the smoking route enables individuals to obtain similar pharmacologic effects as produced by intravenous administration of drug, but without the trauma of needle use. Physiological measures such as pupil diameter were compared to drug and metabolite blood levels. Evidence of delays in distribution to effector sites are observed following marijuana smoking, but drug effects following heroin and cocaine administration coincided more closely with concurrent blood concentrations. Onset to effects are delayed longer following intranasal administration and became pronounced after oral administration.