Toxicology Drugs and Poisons

What is a drug? A drug is a natural or synthetic substance used to produce physiological or psychological effects.

Drug Abuse Drug Abuse has grown from a problem associated with lower social-economical statist to one that affects all social and ethnic classes of society. 75% of all evidence in crime labs is drug related

Why do people use drugs? Desire to create sense of well being Escape from reality Seeking relief from personal problems and stress Maintain a physical or emotional state that improves their level of performance

Drug Dependence Psychological Dependence- conditioned use of a drug caused by underlying emotional needs Physical Dependence- physiological need for a drug that has been brought about by regular use Dependence- characterized by withdraw sickness when drug use is abruptly stopped Drug Abuse is a creation of a psychological dependence

Potential for Psychological Dependence HIGH POTENTIAL- Alcohol, heroin, amphetamines, barbiturates, cocaine, Phenocyclodine (PCP) LOW POTENTIAL- Marijuana, codeine, caffeine, LSD

Potential for Physical Dependence Physical dependence only occurs when the user adheres to a regular schedule of drug use. Intervals between doses is short enough for the effects to never wear off. Physical dependence is not present in all drugs

Potential for Physical Dependence High Potential- Narcotics – morphine, heroine, codeine, Depressants- barbiturates, alcohol, quaalude, valium Nicotine (stimulant) Low Potential- Stimulants- Amphetamines, cocaine, caffeine Hallucinogens- Marijuana, LSD, Phencyclidine (PCP)

Drug Distribution Society must weigh the individual, social, cultural, legal and medical factors to decide to prohibit or impose restrictions on drug distribution Weigh the benefits vs. harm to individuals and society Early laws were designed to control ‘habit-forming’ drugs (mostly opium and marijuana)

Types of Drugs Narcotics - drugs that relieve pain and produce sleep Most narcotics are derived from opium; EX. Heroin & morphine Some are synthetic; Methadone & codeine  

Types of Drugs Hallucinogens - cause marked alterations in normal thought processes, perceptions and moods Include marijuana, LSD, PCP, ecstasy (MDMA) Some fungi also have hallucinogens in them 

Types of Drugs Depressants - Substance that depresses the function of the Central Nervous System. They calm irritability, anxiety, and may induce sleep Include alcohol (ethyl), barbiturates (downers), tranquilizers and glue sniffing 

Types of Drugs Stimulants - substance taken to increase alertness or activity Include amphetamines (speed, uppers), cocaine, caffeine and nicotine

Anabolic Steroids - synthetic form of testosterone In 1991 they were classified as a controlled, dangerous substance

Drug Control Laws Severity of penalty depends on the weight or concentration of drug. This leads to the person being charged with manufacturing, distributing or possessing the drug. US Federal Law- Controlled Substance Act 5 levels (schedules)of classification based on the drug’s potential for abuse, physical and psychological dependency, and medical value.

Drug Control Laws: 5-Levels Schedule I - Punishable by 0-20 years prison and $1 million in fines High potential for abuse, no accepted medical use in US Heroin, marijuana, Quaaludes, LSD   Schedule II - Punishable by 0-20 years prison and $1 million in fines High potential for abuse but some accepted medical use Opium, cocaine, PCP, Amphetamines, Barbiturates Schedule III - Punishable by 0-5 years prison and $250,000 in fines Potential for abuse and currently accepted medical uses Steroids and codeine Schedule IV - Punishable by 0-3 years prison and $250,00 in fines Low potential for abuse, lots of medical uses, limited dependency Valium, tranquilizers, Phenobarbital Schedule V - Punishable by 0-1 year in prison and $100,000 in fines Low potential for abuse, lots of medical uses and very little potential for dependency Opiate drug mixtures and non-narcotic medicines New designer drugs are added as they become known

Drug Identification Start with a screening test - usually color test Once class is determined then more specific testing maybe performed Routine analysis involves color tests, microcrystalline tests, chromatography, spectrophotometry and mass spectrometry

Drug Identification 5 primary color test reagents 1. Marquis - Turns purple in the presence of heroin, morphine and most opium derivatives. Turns orange-brown when mixed with amphetamines and methamphetamines. 2. Dillie-Koppanyi - 2 solution test that turns violet-blue in the presence of barbiturates 3. Duquenois-Levine - 3 solution test that turns purple in the presence of marijuana 4. Van Urk - Turns blue-purple in the presence of LSD 5. Scott Test - 3 solution test. Turns blue after the last solution if cocaine is present

Drug Identification Microcrystalline Tests - A drop of chemical reagent is added a small quantity of the drug. A chemical reaction insures and causes a crystalline precipitate. The size and shape of these crystals can identify the type of drug.   Chromatography - Thin-layer (TLC) and gas chromatography(GC) are also used. These techniques need a comparison between the unknown and known drug so these are used in compliment with the color and crystal tests. Spectrophotometry - UV and IR light are used to produce a spectrum that should be unique between different drugs. The difficulty occurs when the drug is mixed with another substance. The other substance can interfere with the spectrum of the drug component. Mass Spectrometry - An improvement upon the spectrophotometry. This uses electron to bombard the particles until they fragment. No two particles fragment in the same pattern. Used in conjunction with the GC - (GC/MS)