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Chapter 11: Substance Use Disorders. Fall, 2012 Dr. Mary L. Flett, Instructor. Overview. Costs are astronomical DSM uses two terms to describe substance use disorders Substance dependence (more severe) Substance abuse (less severe) Term “addiction” replaced with dependence. Overview.
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Chapter 11: Substance Use Disorders Fall, 2012 Dr. Mary L. Flett, Instructor
Overview • Costs are astronomical • DSM uses two terms to describe substance use disorders • Substance dependence (more severe) • Substance abuse (less severe) • Term “addiction” replaced with dependence
Overview • Drug of abuse (psychoactive substance) is a chemical that alters mood, level of perception or brain functioning • May induce a “high” or alter levels of consciousness • Includes both legal and illegal substances
Overview • Types include • Narcotic analgesics • Cannabinoids • Types include • Depressants of the CNS • Alcohol • Hypnotics • Sedatives • Anxiolitics • Stimulants of the CNS • amphetamine • Cocaine • Nicotine • Caffeine
Overview • Although chemically different in effect, substances share many common elements • Inherent conflict between immediate pleasure and longer-term harmful consequences • Psychological and bio-chemical effects are similar; with negative consequences socially and occupationally • Initial experimentation, transition to dependence, & relapse
Symptoms • No single symptom identifies dependence • Total number of problems individual encounters is a useful distinction between those who are dependent and those who are not • Pathological consumption • consequences following prolonged pattern of abuse • functional impairment • legal and financial problems • deteriorating medical condition • Amount of a substance is not a clear indicator
Symptoms • Craving is associated with dependence • How much time is spent planning to take the drug • Better described as psychological dependence • Need to relieve negative mood states • Compulsion as a need to prepare for certain activities • Attempts to stop are short-lived or end in relapse
Symptoms • Tolerance and withdrawal (physiological dependence) • Tolerance refers to sensitivity to the effects of the substance decrease • Metabolic tolerance (increase in liver enzymes) • Pharmacodynamic tolerance (brain receptors adapt) • Behavioral conditioning (conditioned stimuli) • Some drugs are more likely to produce a build-up of tolerance (heroine, amphetamine, cocaine) • Unclear about weed – most heavy users are not aware of tolerance effects
Symptoms • Withdrawal refers to symptoms experienced when drug is stopped • Symptoms may last several days • Alcohol withdrawal symptoms include • hand tremors • sweating, • nausea, • anxiety • hand tremors • Serious withdrawal symptoms include • hallucinations • delirium (DTs)
Symptoms • Withdrawal symptoms vary considerably for different substances • Caffeine most widely used psychoactive substance in the world • Withdrawal -- headaches
Issues with Alcohol (Etoh) • Affects virtually every organ in your body • Rate of absorption depends on • concentration of Etoh in beverage • volume and rate of consumption • presence of food in the digestive system • Eventually most of the Etoh is broken down in the liver • Rates of metabolism vary person to person • When consumption rate exceeds metabolic limit, blood Etoh levels rise
Issues with Alcohol (Etoh) • Short-term effects • Slurred speech • Lack of coordination • Unsteady gait • Nystagmus • Impaired attention/memory • Stupor or coma
Issues with Alcohol (Etoh) • Short-term effects • Individuals with blood alcohol levels (BAL) between 150-300 mg % will act intoxicated • Neurological and respiratory complications appear at higher levels • BAL >400 mg % may end with coma or toxic shock and death • DUI level in California is 80 mg %
Issues with Alcohol (Etoh) • Long-term consequences • Disruption of relationships • Blackouts • Interference with job performance • Legal problems • DUI • Spousal/child abuse • Violent behavior
Issues with Alcohol (Etoh) • Long-term consequences • Biological problems • Liver, pancreas, gastrointestinal system, cardiovascular, endocrine system disorders • Cirrhosis of the liver • Cancer • Dementia (Korsakoff’s Syndrome) • Nutritional problems • Injuries and deaths
Issues with Nicotine • Toxic in its pure form; only source of nicotine is tobacco plant • Smoking or chewing provide a diluted concentration better tolerated than high doses • When smoked, nicotine is absorbed into the bloodstream through the mucous membranes in the lungs • Carried directly to the heart and brain resulting in the highest concentration of nicotine
Issues with Nicotine • Short-term effects • Increased heart rate and blood pressure • Stimulates release of norepinephrine • Stimulates release of dopamine and norepinephrine in the mesolimbic dopamine pathway (reward system of the brain) • Influences serotonin; may mimic antidepressants
Issues with Nicotine • Short-term effects • Complex influence on subjective mood states • May lower experience of stress • Paradoxical response, since it is a CNS stimulator! • Hard to explain – may be relieving withdrawal symptoms
Issues with Nicotine • Long-term Consequences • Harmful and deadly drug • Tolerance and withdrawal in people who smoke and chew • Withdrawal includes drowsiness, lightheadedness, headache, muscle tremors, nausea, sleep problems, weight gain (modest), mood swings, irritability • Symptoms may last for months • At higher risk for developing fatal diseases (CVD, bronchitis, emphysema, cancer)
Issues with Amphetamine & Cocaine • Psychomotor stimulants produce their effects by simulating epinephrine, norepinephrine, dopamine, and serotonin • Dexedrine and meth are produced synthetically • Cocaine is a naturally occurring substance extracted from the leaves of the Coca plant (Erythroxylum coca var. coca)
Issues with Amphetamine & Cocaine • May be taken orally, injected, inhaled • Easier to maintain constant blood level when ingested (absorbed through digestive system) • Dramatic effects when injected or sniffed (blood-brain barrier) • Free-basing – drug is heated and vapors are inhaled • Dangerous because of chemical volatility
Issues with Amphetamine & Cocaine • Short-term Effects • Activate sympathetic nervous system • Increase heart rate, dilate blood vessels and air passages • Suppress appetite • Prevent sleep • May lead to dizziness, confusion, panic states • Induce a positive mood state • Feel more confident, friendly, energetic • Prolonged use may lead to sexual dysfunction; many believe it heightens sexual pleasure
Issues with Amphetamine & Cocaine • Short-term Effects • Feelings of exhilaration are followed by lethargy, depressed and/or irritable mood within 1-2 hours after ingestion • Acute overdoses result in • Irregular heartbeat (tachycardia) • Convulsions • Coma and possibly death
Issues with Amphetamine & Cocaine • Long-term Consequences • High doses lead to onset of psychosis • Risk increases with repeated use • May disappear a few days after drug is cleared from the system • Increase severity for those who already have psychosis • Symptoms include auditory and visual hallucinations, as well as delusions of persecution and grandeur
Issues with Amphetamine & Cocaine • Long-term Consequences • Disruption of social and occupational functioning • Compulsive behaviors • Expensive habit leads to loss of money and resorting to stealing • Linked to increase in violent behavior • Withdrawal does not typically include severe symptoms • Most common symptom is depression/suicidality
Issues with Opiates • Main active ingredients in opiates are morphine and codeine • Effect pain relievers • Heroine is synthetic • May be taken orally, injected, or inhaled • Used in medicine for pain management • Not addictive if used in proper quantities
Issues with Opiates • Short-term Effects • Induces a pleasant, dreamlike euphoria • Increased sensitivity to sight and sound • Heroine rush – brief intense feeling of pleasure (orgasm) • Positive induced mood state does not last; replaced by long-lasting negative mood states • May induce nausea, pupil constriction, disrupt digestive system • Decreases sex drive in males and females • Overdose • Comatose state, depressed respiration, convulsions
Issues with Opiates • Long-term Consequences • Chronic lethargy; lose motivation to be productive • Financial burden; methadone alternative • Chasing the rush • Serious health consequences are result of lifestyle, not substance • HIV/AIDS, STDs, nutrition, homelessness
Issues with Barbiturates & Benzodiazepines • Prescription drugs that address • Anxiety or agitation (tranquilizers) • Sleep problems (hypnotics) • Calm people; reduce excitement (sedative)
Issues with Barbiturates & Benzodiazepines • Short-term Effects • Sedatives & hypnotics may lead to a state of intoxication • Impaired judgment • slowness of speech • lack of coordination • narrowed range of attention • disinhibition of sexual and aggressive impulses • Tranquilizers may lead to “rage reaction” (benzodiazepines)
Issues with Barbiturates & Benzodiazepines • Long-term Consequences • Abrupt stopping of benzo’s may lead to discontinuance syndrome • Return and possibly worsening of original symptoms • May develop new symptoms associated with withdrawal • Irritability • Paranoia • Sleep disturbance • Agitation • Muscle tension • Restlessness • Perceptual disturbances (hallucinations)
Issues with Weed • Active ingredient is THC • Metabolized in the liver • Marijuana = leaves and seeds of the plant • Hash = dried resin from top of female plant • Taken orally or inhaled • Ingestion leads to slow and incomplete absorption requiring 2-3Xs the amount to get high
Issues with Weed • Short-term Effects • Pervasive sense of well-being and happiness • Some may experience anxiety or paranoia • Behavior is easily influenced by others • Intoxication accompanied by forgetfulness and organizing activities • Lapses in attention and concentration • The “Munchies”
Issues with Weed • Long-term Consequences • Tolerance effects are ambiguous • Unlikely to develop tolerance unless exposed to high doses over an extended period • Reverse tolerance (becoming less sensitive) is anecdotally reported but not confirmed in laboratory studies • Withdrawal is unlikely for occasional users; may result in irritability, restlessness, and insomnia for chronic users • Prolonged, heavy use may lead to deficits in sustained attention, learning, and decision making in some
Issues with Hallucinogens • Different kinds cause different effects • Some are similar to chemical structure of serotonin (LSD, psilocybin) and norepinephrine (mescaline) • MDMA is similar to amphetamine • PCP is a synthetic drug originally created for pain management • High doses may induce psychotic episodes
Issues with Hallucinogens • Short-term Effects • Difficult to study; subjective reports • May experience “bad trips” • Unpleasant; may lead to panic attacks • Fear of losing one’s mind • Not particularly toxic • High doses may lead to coma, respiratory arrest • MDMA can permanently damage serotonin neurons
Issues with Hallucinogens • Long-term Consequences • Typical use is sporadic; not chronic • Most people do not increase use over time • Perceptual effects usually diminish or disappear within 2-3 hours • May experience flashbacks
Diagnosis* • Attitudes toward drinking have varied over time and within cultures • Drunkenness in Colonial times was not considered social deviant or symptomatic of mental illness • Temperance Movement in 19th Century changed Americans’ alcohol consumption • Culminated in passage of the 18th Amendment • Prohibition repealed in 1933
Diagnosis • DSM lists 11 types of drugs with generic set of criteria to determine dependence or abuse • Dependence is defined: • Tolerance and withdrawal • Additional specification for physiological dependence • Advantages: unified view of addiction • Disadvantages • Misses some problems between different classes
Diagnosis • Substance abuse is defined in terms of harmful consequences in the absence of tolerance, withdrawal, or a pattern of compulsive use • What is boundary between “recreational use” and abuse? • DSM uses terms “recurrent” and “maladaptive pattern” to distinguish
Diagnosis • Course and Outcome • Impossible to plot a “typical” course/outcome • Age of onset varies • Stages may be predictable, but movement through phases varies • One observable criteria is periods of heavy use are followed by periods of relative abstinence • Controlled drinking • Relapse rates may stabilize over time; need more research
Diagnosis • Comorbid Disorders • Antisocial personality disorder • Mood/Anxiety disorders
Frequency • Use of specific drugs is based on availability • Opium mostly used in SE Asia and Afghanistan • Cocaine mostly used in South America • Weed – throughout the world! • Amphetamine (synthetic) – Japan • Availability does not correlate with prevalence • Not everybody who drinks or uses a substance will become an abuser or dependent • Age of first use is a strong indicator of who will have problems later
Frequency • Patterns of Etoh use (age cohorts) • Adolescents (12-17) have high rates of use • 2 out of 3 males in Western countries drink on a regular basis; 20% will develop a problem • 60% of American women drink Etoh at least occasionally; fewer develop alcoholism • Culture is less tolerant of a drunken woman • Women tend to drink in private; men in public • Males metabolize Etoh differently; higher total body H2O
Frequency • Patterns of Drug & Nicotine Dependence • Approximately 10% of the population has problems with controlled substances • 24% of the population is addicted to nicotine • Smoking is on decline, particularly for men • Rates of smoking increased for 18-25 yo’s in the 1990’s • Tobacco consumption increased dramatically outside the US
Frequency • Risk of Addiction over Lifespan • Fewer elders have problems with Etoh, but many do with prescriptions medications • Tolerance and withdrawal symptoms are quite different in elders who may have comorbid, chronic conditions
Causes • Social Factors • Cultures that prohibit or restrict alcohol have lower rates of alcoholism • Peer pressure • Initial experimentation occurs among the rebellious or extroverted • Parents model use behaviors
Causes • Biological Factors • Physiological responses due to genetic variants in ADH and ALDH genes (metabolism) act as deterrents • flushed skin • tachycardia • Twin studies and Adoption studies strongly suggest a genetic predisposition toward alcoholism; may also include environmental influences
Causes • Neuroanatomy & Neurochemistry • Well studied and understood • Reward pathways (p. 345)