Flashcards in Substance Abuse Deck (32)
DRUGS OF ABUSE
There are many misunderstandings about the origins and even the definitions of drug abuse and dependence. Although many physicians are concerned about “ creating addicts” only few individuals begin their drug addiction problems by misuse of prescription drugs. Confusion exists because the correct use of prescription drugs for pain, anxiety, and even hypertension commonly produces tolerance and physical dependence. These are normal physiological adaptations to repeated use of drugs from many different categories. Therefore tolerance and physical dependence do not imply abuse or addiction.
tolerance & dependence
While tolerance and physical dependence are biological phenomena that can be defined precisely in the laboratory and diagnosed accurately in the clinic, there is an arbitrary aspect to the definitions of the overall behavioral syndromes. Therefore the American Psychiatric Association diagnostic system uses the term substance dependence instead of addiction for the overall behavioral syndrome.
The APA defines substance dependence as a cluster of symptoms indicating that the individual continues use of the substance despite significant substance-related problems.
ORIGINS of SUBSTANCE DEPENDENCE
Many variables operate simultaneously to influence the likelihood of any given person becoming a drug abuser or drug dependent. These variables can be organized into three categories:
(1) agent (drug)
(2) host (user)
1) agent (drug)
Drugs vary in their ability to produce immediate good feelings in the user. Drugs that reliably produce intensely pleasant feelings (euphoria) are more likely to be taken repeatedly.
Reinforcement refers to the ability of drugs to produce effects that make the user wish to take them again. The more strongly reinforcing a drug is, the greater the likelihood that the drug will be abused. Reinforcing properties of drugs are associated with the ability to increase levels of neurotransmitters.
The abuse liability of a drug is enhanced by rapidity of onset, since effects that occur soon after administration are more likely to initiate the chain of events that lead to loss of control over drug taking.
-mode of administration
-speed of onset and termination of effects
(2) Host (user)
-speed of developing acquired tolerance
-likelihood of experiencing intoxication as pleasure
-propensity for risk-taking behavior
-peer influence, role models
-availability of other reinforcers
Physical dependence is state that develops as a result of the adaptation (tolerance) produced by a resetting of homeostatic mechanisms in response to repeated drug use.
Drugs can affect numerous systems that previously in equilibrium: these systems must find a new balance in the presence of inhibition or stimulation by a specific drug. A person in this adapted or physically dependent state requires continued administration of the drug to maintain normal function. If administration of the drug is stopped abruptly, there is another imbalance and the affected system must go through a process of readjusting to a new equilibrium without the drug.
The appearance of a withdrawal syndrome when the drug is terminated is the only actual evidence of physical dependence.
HEROIN, MORPHINE, MEPERIDENE, FENTANYL,OXYCODONE, OPIUM
Routes of Administration: I.V., intranasal, smoked
Some of the CNS mechanisms that reduce the perception of pain also produce a state of well-being or euphoria. Therefore, opioid drugs are taken outside of medical channels for the purpose of obtaining the effects on mood.
Overdose: respiratory depression
opiod withdrawal & detox
Anxiety & depression, sleep disturbance, nausea & vomiting, sweating, diarrhea, abdominal cramping, tachycardia & hypertension, mydriasis (except meperidine).
Detoxification from opioids
(A) clonidine- clonidine can attenuate the noradrenergic hyperactivity of opiate withdrawal without interfering significantly with activity at the opiate receptors (receptors can return to normal levels of sensitivity). An advantage of clonidine vs. methadone, is no euphoria associated with clonidine. Also given with naltrexone
``(C) buprenorphine (Subutex) partial mu agonist with naloxone (Suboxone)
Amphetamine, Methamphetamine, Methylphenidate, Cocaine
The central nervous system (CNS) actions that result from taking stimulants include: increased wakefulness, increased physical activity, decreased appetite, increased respiration, hyperthermia, and euphoria. Other CNS effects include irritability, insomnia, confusion, tremors, convulsions, anxiety, paranoia, and aggressiveness. Hyperthermia and convulsions can result in death.
effects of stimulants
Stimulants causes increased heart rate and blood pressure and can cause irreversible damage to blood vessels in the brain, producing strokes. Other effects of methamphetamine include respiratory problems, irregular heartbeat, and extreme anorexia. Its use can result in cardiovascular collapse and death.
Studies have shown that methamphetamine destroys dopaminergic neurons in the striatum---could lead to what disease state____________???
(1)Hallucinogenic agents-LSD, Psilocybin,
(2) Mixed stimulant & hallucinogenic- MDA, MDMA (Ecstasy), mescaline
(3) Phencyclidine (PCP)
LSD (lysergic acid diethylamide) is one of the major drugs making up the hallucinogen class. LSD was discovered in 1938 and is one of the most potent mood-changing chemicals. It is manufactured from lysergic acid, which is found in ergot, a fungus that grows on rye and other grains.
LSD, commonly referred to as "acid," is sold on the street in tablets, capsules, and, occasionally, liquid form. It is odorless, colorless, and has a slightly bitter taste and is usually taken by mouth. Often LSD is added to absorbent paper, such as blotter paper, and divided into small decorated squares, with each square representing one dose.
The effects of LSD are unpredictable. They depend on the amount taken; the user's personality, mood, and expectations; and the surroundings in which the drug is used. Usually, the user feels the first effects of the drug 30 to 90 minutes after taking it. The physical effects include dilated pupils, higher body temperature, increased heart rate and blood pressure, sweating, loss of appetite, sleeplessness, dry mouth, and tremors.
Sensations and feelings change much more dramatically than the physical signs. The user may feel several different emotions at once or swing rapidly from one emotion to another. If taken in a large enough dose, the drug produces delusions and visual hallucinations. The user's sense of time and self changes. Sensations may seem to "cross over," giving the user the feeling of hearing colors and seeing sounds. These changes can be frightening and can cause panic.
Users refer to their experience with LSD as a "trip" and to acute adverse reactions as a "bad trip." These experiences are long - typically they begin to clear after about 12 hours.
Some LSD users experience severe, terrifying thoughts and feelings, fear of losing control, fear of insanity and death, and despair while using LSD. Some fatal accidents have occurred during states of LSD intoxication.
Hallucinogen Persisting Perception Disorder (HPPD)
LSD users experience flashbacks, recurrence of certain aspects of a person's experience, without the user having taken the drug again. A flashback occurs suddenly, often without warning, and may occur within a few days or more than a year after LSD use. Flashbacks usually occur in people who use hallucinogens chronically or have an underlying personality problem; however, otherwise healthy people who use LSD occasionally may also have flashbacks. Bad trips and flashbacks are only part of the risks of LSD use. LSD users may manifest relatively long-lasting psychoses, such as schizophrenia or severe depression.
*******LSD is not a reinforcer, nor is there physical dependence, or withdrawal. **********
Mixed stimulant & hallucinogenic
MDMA is a synthetic, psychoactive drug with both stimulant (amphetamine-like) and hallucinogenic (LSD-like) properties. Street names for MDMA include Ecstasy, Adam, XTC, hug, beans, and love drug. Its chemical structure (3-4 methylenedioxymethamphetamine, "MDMA") is similar to methamphetamine, methylenedioxyamphetamine (MDA), and mescaline - other synthetic drugs known to cause brain damage.
MDMA also is neurotoxic. In addition, in high doses it can cause a sharp increase in body temperature (malignant hyperthermia----which drug to treat_____________??) leading to muscle breakdown and kidney and cardiovascular system failure.
NMDA Health Hazards
Brain imaging research in humans indicates that MDMA causes injury to the brain, affecting neurons that use the chemical serotonin to communicate with other neurons. The serotonin system plays a direct role in regulating mood, aggression, sexual activity, sleep, and sensitivity to pain. Many of the risks users face with MDMA use are similar to those found with the use of cocaine and amphetamines:
Psychological difficulties, including confusion, depression, sleep problems, drug craving, severe anxiety, and paranoia - during and sometimes weeks after taking MDMA.
Physical symptoms such as muscle tension, involuntary teeth clenching, nausea, blurred vision, rapid eye movement, faintness, and chills or sweating.
Increases in heart rate and blood pressure, a special risk for people with circulatory or heart disease.
Also, there is evidence that people who develop a rash that looks like acne after using MDMA may be risking severe side effects, including liver damage, if they continue to use the drug.
Research links MDMA use to long-term damage to those parts of the brain critical to thought and memory. One study, in primates, showed that exposure to MDMA for 4 days caused brain damage that was evident 6 to 7 years later.
Ketamine is an anesthetic (Which kind of anesthesia___________?) that has been approved for both human and animal use in medical settings since 1970; about 90 percent of the ketamine legally sold is intended for veterinary use. It can be injected or snorted. Ketamine is also known as "Special K" or "vitamin K".
Certain doses of ketamine can cause dream-like states and hallucinations, and it has become common in club and rave scenes and has been used as a date rape drug.
At high doses, ketamine can cause delirium, amnesia, impaired motor function, high blood pressure, depression, and potentially fatal respiratory problems.
PCP (phencyclidine) was developed in the 1950s as an intravenous anesthetic. Use of PCP in humans was discontinued in 1965, because it was found that patients often became agitated, delusional, and irrational while recovering from its anesthetic effects. PCP is illegally manufactured in laboratories and is sold on the street by such names as "angel dust," "ozone," "wack," and "rocket fuel." "Killer joints"and "crystal supergrass" are names that refer to PCP combined with marijuana. The variety of street names for PCP reflects its bizarre and volatile effects
PCP is a white crystalline powder that is readily soluble in water or alcohol. It has a distinctive bitter chemical taste. PCP can be mixed easily with dyes and turns up on the illicit drug market in a variety of tablets, capsules, and colored powders. It is normally used in one of three ways: snorted, smoked, or eaten. For smoking, PCP is often applied to a leafy material such as mint, parsley, oregano, or marijuana
PCP binds with high affinity to sites located in the cortex and limbic structure, resulting in the blocking of N-methyl-D-aspartic acid (NMDA)- type glutamate receptors and sigma opiate receptors
PCP health hazards
PCP use often leads to psychological dependence, craving, and compulsive drug-seeking behavior. It was first introduced as a street drug in the 1960s and quickly gained a reputation as a drug that could cause bad reactions and was not worth the risk. Many people, after using the drug once, will not knowingly use it again. Yet others use it consistently and regularly. Some persist in using PCP because of its reinforcing properties. Others cite feelings of strength, power, invulnerability and a numbing effect on the mind as reasons for their continued PCP use.
Many PCP users are brought to emergency rooms because of PCP's unpleasant psychological effects or because of overdoses. In a hospital or detention setting, they often become violent or suicidal, and are very dangerous to themselves and to others. They should be kept in a calm setting and should not be left alone.
Psychological effects at high doses include illusions and hallucinations. PCP can cause effects that mimic the full range of symptoms of schizophrenia, such as delusions, paranoia, disordered thinking, a sensation of distance from one's environment, and catatonia. Speech is often sparse and garbled.
Since about 1990, GHB (gamma hydroxybutyrate) has been abused in the U.S. for euphoric, sedative, and anabolic (body building) effects. It is a central nervous system depressant that was widely available over-the-counter in health food stores during the 1980s and until 1992. It was purchased largely by body builders to aid fat reduction and muscle building. Street names include Liquid Ecstasy, Soap, Easy Lay, and Georgia Home Boy.
Coma and seizures can occur following abuse of GHB and, when combined with methamphetamine, there appears to be an increased risk of seizure. Combining use with other drugs such as alcohol can result in nausea and difficulty breathing. GHB may also produce withdrawal effects, including insomnia, anxiety, tremors, and sweating.
GHB and two of its precursors, gamma butyrolactone (GBL) and 1,4 butanediol (BD) have been involved in poisonings, overdoses, date rapes, and deaths. These products, obtainable over the internet and sometimes still sold in health food stores, are also available at some gyms, raves, nightclubs, college campuses, and the street. They are commonly mixed with alcohol (which may cause unconsciousness), have a short duration of action, and are not easily detectable on routine hospital toxicology screens.
Rohypnol, a trade name for flunitrazepam ( which class____________), has been of particular concern for the last few years because of its abuse in date rape. When mixed with alcohol, Rohypnol can incapacitate victims and prevent them from resisting sexual assault. It can produce "anterograde amnesia," which means individuals may not remember events they experienced while under the effects of the drugs. Also, Rohypnol may be lethal when mixed with alcohol and/or other depressants.
Rohypnol is not approved for use in the United States, and its importation is banned. Illicit use of Rohypnol started appearing in the United States in the early 1990s, where it became known as "rophies," "roofies," "roach," and "rope."
Marijuana is a green or gray mixture of dried, shredded flowers and leaves of the hemp plant Cannabis sativa. There are over 200 slang terms for marijuana including "pot," "herb," "weed," "boom," "Mary Jane," "gangster," and "chronic." It is usually smoked as a cigarette (called a joint or a nail) or in a pipe or bong. In recent years, marijuana has appeared in blunts, which are cigars that have been emptied of tobacco and refilled with marijuana, often in combination with another drug, such as crack. Some users also mix marijuana into foods or use it to brew tea.
main chemical in marijuana
The main active chemical in marijuana is THC (delta-9-tetrahydrocannabinol). In 1988, it was discovered that the membranes of certain nerve cells contain protein receptors that bind THC. Once bound to THC receptors, a series of cellular reactions take place that ultimately lead to the high that users experience when they smoke marijuana. The short term effects of marijuana use include problems with memory and learning; distorted perception; difficulty in thinking and problem-solving; loss of coordination; and increased heart rate, anxiety, and panic attacks.
Effects of Marijuana on the Brain
Researchers have found that THC changes the way in which sensory information gets into and is processed by the hippocampus, a component of the brain's limbic system that is crucial for learning, memory, and the integration of sensory experiences with emotions and motivations. Investigations have shown that neurons in the information processing system of the hippocampus and the activity of the nerve fibers in this region are suppressed by THC. In addition, researchers have discovered that learned behaviors, which depend on the hippocampus, also deteriorate via this mechanism.
Effects of mariguana on the lungs
Someone who smokes marijuana regularly may have many of the same respiratory problems as tobacco smokers. These individuals may have daily cough and phlegm, symptoms of chronic bronchitis, and more frequent chest colds. Continuing to smoke marijuana can lead to abnormal functioning of lung tissue injured or destroyed by marijuana smoke.
Regardless of the THC content, the amount of tar inhaled by marijuana smokers and the level of carbon monoxide absorbed are three to five times greater than among tobacco smokers. This may be due to the marijuana users' inhaling more deeply and holding the smoke in the lungs and because marijuana smoke is unfiltered.