Uppers Downers & All Arounders. Chapter 2, Part II. Physiological Responses to Drugs. Determines how drugs affect people and why it is difficult to control their levels of use. They include: Tolerance to Drug Tissue Dependence Psychological Dependence & Reward-reinforcing action of drugs
Chapter 2, Part II
The liver is most responsible for metabolizing, detoxi-fying, and eliminating drugs. The drug-laden blood enters through the portal vein, is processed by various enzymes, and then sent via the hepatic vein to the heart where it is then pumped to the rest of the body. If the alcohol and another depressant drug are taken together, they compete for the same enzymes so the liver allows the other to enter the circulatory system at full strength.
SPECT stands for single photon emission computerized tomography, a method for imaging the activity of the brain. It shows areas of activity and inactivity. The “holes” in the brain are actually areas that are inactivated by the use of a drug or the practice of some behavior. Abstinence will restore much but not all of the brain function. The more chronic the use, the less restoration of activity. Methamphetamine is more toxic than heroin or cocaine.
Alcohol is a protoplasmic poison, so much of the inactivation in the brain of a chronic alcoholic can be long lasting. Heroin is less toxic to brain cells, so abstinence will restore more brain function