Drugs & Toxicology

1. Drugs & Toxicology Chapters 9 & 10

2. Drugs • Are natural or synthetic substances designed to affect the subject psychologically or physiologically

3. Narcotic Drugs • Are analgesics, meaning they relieve pain by a depressing action on the central nervous system • Effects blood pressure, pulse rate, and breathing rate • Regular use can lead to physical dependence • Most common narcotic drugs are the opiates

4. Heroin • Morphine is readily extracted from opium and is used to synthesize heroin • Addicts frequently dissolve heroin in water by heating it in a spoon and then injecting in the skin • Heroin produces a “high” that is accompanied by drowsiness and a sense of well being that generally lasts 3-4 hours

5. Codeine • Also present in opium, but it is usually prepared synthetically from morphine

6. Oxycontin • Is not derived from opium or morphine • It does have the same physiological effects on the body as do opium narcotics • Is prescribed to a million patients for treatment with chronic pain

7. Methadone • Is a well known synthetic opiate • Is pharmacologically related to heroin • Eliminates the addict’s desire for heroin while producing minimal side effects

8. Hallucinogens • Marijuana is the most well known member of the class • Cause marked changes in normal thought processes, perceptions, and moods • Marijuana is the most controversial drug in this class because its long term effects on health are still largely unknown

10. Marijuana • Refers to the preparation derived from the plant Cannabis • The chemical substance largely responsible for the hallucinogenic properties of marijuana is tetrahydrocannabinol, or THC • THC content varies in different parts of the plant, generally decreasing in the following sequence: resin, flowers, leaves, with little THC in the stem, roots, or seeds

11. Marijuana • The THC rich resin is known as hashish • Marijuana does not cause physical dependency, but the risk of harm is in heavy, long term use

12. Other Hallucinogens • Include LSD, mescaline, PCP, psilocybin, and MDMA (ecstasy)

13. LSD • Is synthesized form lysergic acid, and can cause hallucinations that can last for 12 hours

14. PCP • AKA phencyclidine • Is often synthesized in clandestine laboratories and is often smoked, ingested, or sniffed • Is often mixed with other drugs such as LSD or amphetamine and is sold as a powder (angel dust), capsule, or tablet • Oral intake of PCP first leads to feelings of strength and invulnerability, which may turn to depression, tendencies toward violence, and suicide

15. Depressants • Are another class of drugs • Are substances used to depress the functions of the central nervous system • Calm irritability and anxiety and may induce sleep • Include alcohol (ethanol), barbiturates, tranquilizers, and various substances that can be sniffed, such as airplane glue, model cement, or aerosol gas propellants such as freon

16. Alcohol • Enters the body’s bloodstream and quickly travels to the brain where it acts to suppress the brain’s control of though processes and muscle coordination

17. Barbiturates • AKA downers • Are normally taken orally • Create a feeling of well being, relax the body, and produce sleep

18. Tranquilizers • Produce a relaxing tranquility without impairment of high thinking faculties or inducing sleep

19. Sniffing • Has immediate effects such as exhilaration, but impairs judgment and may cause liver, heart, and brain damage or even death

20. Stimulants • Are substances taken to increase alertness or activity, followed by a decrease in fatigue and a loss of appetite • Includes amphetamines, sometimes known as “uppers” or “speed”, and cocaine, which in its free base form is known as crack

21. Amphetamines • Amphetamines and methamphetamines often are injected intravenously • Cause an initial rush followed by an intense feeling of pleasure that is followed by a period of exhaustion and a prolonged period of depression

22. Cocaine • Is extracted from the leaves of Erythroxylin coca • Causes increased alertness and vigor, accompanied by the suppression of hunger, fatigue, and boredom

23. Crack • Is cocaine mixed with baking soda and water, then heated • Is often smoked in glass pipes, and like cocaine, stimulates the brain’s pleasure center

24. Club Drugs • Refers to synthetic drugs that are used at nightclubs, bars, and raves • Substances that are often used as club drugs include, but are not limited to, MDMA (ectasy), GHB (gamma hydroxybutyrate), Rohypnol (Roofies), ketamine, and methamphetamine

25. Ecstasy • AKA methylenedioxymethamphetamine • Is a synthetic mind altering drug that exhibits many hallucinogenic and amphetamine-like effects • Enhances self awareness and decreases inhibitions • Seizures, muscle breakdown, stroke, kidney failure, and cardiovascular system failure often accompany chronic abuse

26. GHB & Rohypnol • Are central nervous system depressants that are often connected with drug facilitated sexual assault, rape, and robbery

27. Ketamine • Is primarily used as a veterinary animal anesthetic that in humans causes euphoria and hallucinogens • Can also cause impaired motor functions, high blood pressure, amnesia, and mild respiratory depression

28. Anabolic Steroids • Are synthetic compounds that are chemically related to the male sex hormone testosterone • Are often abused by individuals who are interested in accelerating muscle growth • Side effects include unpredictable effects on mood and personality, depression, diminished sex drive, halting bone growth, and liver cancer

29. Toxicology • Is the study of the adverse effects of chemicals or physical agents on living organisms

30. Toxicologists • Toxicologists are charged with the responsibility for detecting and identifying the presence of drugs and poisons in body fluids, tissues, and organs • Work in crime labs and medical examiners offices, but may also reach into hospital labs and health care facilities to identify a drug overdose or monitor the intake of drugs

31. Toxicology • Toxic substances may • Be a cause of death • Continue to death • Cause impairment • Explain behavior

32. Aspects of Toxicology • Dosage • The chemical or physical form of the substance • The mode of entry into the body • Body weight and physiological conditions of the victim, including age and sex • The time period of exposure • The presence of other chemicals in the body or in the dose

33. Lethal Dose • LD50 • Refers to the dose of a substance that kills half the test population, usually within 4 hours • Expressed in milligrams of substance per kilogram of body weight

34. Symptoms of Poisoning

35. To Prove a Case • Prove a crime was committed • Motive • Intent • Access to poison • Access to victim • Death was caused by poison • Death was homicidal

36. Forensic Autopsy • Look for • Irritated tissues • Characteristic odors • Mees line • Single transverse white bands on nails • Order toxicological screens • Postmortem concentrations should be done at the scene for comparison • No realistic calculation of dose can be made from a single measurement

37. Human Specimens for Analysis • Blood • Urine • Vitreous humor of eye • Bile • Gastric contents • Liver tissue • Brain tissue • Kidney tissue • Hair • Nails

38. Toxicology of Alcohol • Alcohol, or ethyl alcohol, is a colorless liquid normally diluted with water and consumed as a beverage • It is the most abused drug • Like any depressant, alcohol principally effects the central nervous system, particularly the brain • 40% of all traffic deaths are alcohol related • About 5% is excreted unchanged in breath, perspiration, and urine • 90% is detoxified by the liver

39. Toxicology of Alcohol • Alcohol appears in the blood within minutes after it has been taken by mouth and slowly increases in concentration while it is being absorbed from the stomach and the small intestine into the bloodstream • It takes 30 –90 minutes for full absorption

40. Rate of Absorption • Depends on • Time taken to consume the drink • The alcohol content • The amount of alcohol consumed • Food present in the stomach • Physiology of the consumer

41. Blood Alcohol Content • The extent to which the individual may be under the influence of alcohol is usually determined by either measuring the quantity of alcohol present in the blood system or by measuring the alcohol content in the breath • Is expressed as percent weight per volume of blood • Legal limits in all states is 0.08%

42. Blood Alcohol Content • Parameters affecting BAC • Body weight • Alcoholic content • Number of beverages consumed • Time between consumption

43. Blood Alcohol Content • Burn off rate of 0.015% per hour but can vary • Male • BAC Male= 0.071 x (# oz) x (% alcohol)/ body weight • Female • BAC Female= 0.085 x (# oz) x (% alcohol)/body weight

44. Field Tests • Preliminary tests • Used to determine the degree of suspect’s physical impairment and whether or not another test is justified • Psychophysical tests • 3 basic tests exist • Horizontal gaze nystagmus (HGN) • Nine step walk and turn (WAT) • One leg stand (OLS)

45. Field Tests • Horizontal gaze nystagmus (HGN • Follow a pen or small flashlight, tracking left to right with one’s eyes • Wavering at 45 degrees indicates BAC of 0.10 • Nine step walk and turn (WAT) • Comprehend and execute two or more simple instructions at a time • One leg stand (OLS) • Maintain balance, comprehend and execute two or more simple instructions at one time

46. The Breathalyzer • More practical in the field • Collects and measures alcohol content of alveolar breath • Breath sample mixes with 3 ml of 0.025% potassium dichromate in sulfuric acid and water • Measures light absorption of potassium dichromate before and after the reaction with alcohol

47. Controlled Substances • Are drugs that are restricted by law • Law was enacted in 1970 listing illegal drugs, their category and their penalty for possession, sale or use • Called Controlled Substances Act • Was created to prevent and control drug use

48. Controlled Substances Act • Established 5 schedules of classification for controlled dangerous substances on the basis of a drug’s • Potential for abuse • Potential for physical and psychological dependence • Medical value

49. Schedule I Drugs • High potential for abuse • No currently acceptable medical use in the US • A lack of accepted safety for use under medical supervision • Includes marijuana, heroin, ecstasy, and LSD

50. Schedule II Drugs • High potential for abuse • A currently accepted medical use with severe restrictions • Abuse may lead to severe psychological or physical dependence • Include cocaine, PCP, morphine, amphetamines, methamphetamines, ritalin