hart13 ppt ch06
DESCRIPTION
(c) McGraw-Hill 2011TRANSCRIPT
© 2011 McGraw-Hill Higher Education. All rights reserved.
Chapter 6Chapter 6
StimulantsStimulants
© 2011 McGraw-Hill Higher Education. All rights reserved.
StimulantsStimulants
Stimulants are substances Stimulants are substances that keep a person going that keep a person going mentally and physicallymentally and physically
Cocaine and amphetamine Cocaine and amphetamine are restricted stimulantsare restricted stimulants
Caffeine and nicotine are Caffeine and nicotine are readily available stimulants readily available stimulants
© 2011 McGraw-Hill Higher Education. All rights reserved.
History of CocaineHistory of Cocaine
Coca is a bush that grows in the Andes and Coca is a bush that grows in the Andes and produces cocaineproduces cocaine Coca has been harvested for thousands of years Coca has been harvested for thousands of years
and actively cultivated for over 800 yearsand actively cultivated for over 800 years
© 2011 McGraw-Hill Higher Education. All rights reserved.
History of CocaineHistory of Cocaine
Natives of the Andes chewed Natives of the Andes chewed coca leaves to give them coca leaves to give them greater strength and greater strength and endurance endurance
The coca leaf was an The coca leaf was an important part of Inca cultureimportant part of Inca culture Used in religious ceremonies Used in religious ceremonies
and as currency and as currency
Coca leaf market
© 2011 McGraw-Hill Higher Education. All rights reserved.
History of CocaineHistory of Cocaine
Coca wine:Coca wine: Angelo Mariani Angelo Mariani Used coca leaf extract in many Used coca leaf extract in many
products including lozenges, products including lozenges, tea, and, especially, winetea, and, especially, wine
© 2011 McGraw-Hill Higher Education. All rights reserved.
History of CocaineHistory of Cocaine
Coca extract was later used in the United States in early Coca extract was later used in the United States in early versions of Coca-Cola and in many patent medicinesversions of Coca-Cola and in many patent medicines
© 2011 McGraw-Hill Higher Education. All rights reserved.
History of CocaineHistory of Cocaine
Local anesthesia:Local anesthesia: Dr. W. S. Halsted Dr. W. S. Halsted Experimented with ability of cocaine to produce Experimented with ability of cocaine to produce
local anesthesialocal anesthesia Delivered via newly developed hypodermic syringeDelivered via newly developed hypodermic syringe
Cocaine was isolated Cocaine was isolated before 1860before 1860
Processing 500 kilograms Processing 500 kilograms of coca leaves yieldsof coca leaves yields1 kilogram of cocaine 1 kilogram of cocaine
Drying coca leaves
© 2011 McGraw-Hill Higher Education. All rights reserved.
History of CocaineHistory of Cocaine
Early psychiatric uses:Early psychiatric uses:Sigmund Freud Sigmund Freud Studied use of cocaine as a treatment for Studied use of cocaine as a treatment for
depression and morphine dependencedepression and morphine dependence Later opposed use of the drug after nursing Later opposed use of the drug after nursing
a friend through cocaine psychosisa friend through cocaine psychosis
© 2011 McGraw-Hill Higher Education. All rights reserved.
Early Legal ControlEarly Legal Control
46 states passed laws to regulate cocaine 46 states passed laws to regulate cocaine between 1887 and 1914between 1887 and 1914
Press and politicians made unsubstantiated Press and politicians made unsubstantiated claims about cocaine use among southern claims about cocaine use among southern blacks: blacks: Widespread Widespread Associated with increased violent crimeAssociated with increased violent crime
Negative publicity about cocaine influenced Negative publicity about cocaine influenced the passage of the 1914 Harrison Actthe passage of the 1914 Harrison Act
© 2011 McGraw-Hill Higher Education. All rights reserved.
Forms of CocaineForms of Cocaine
Coca pasteCoca paste Crude extract created during the Crude extract created during the
manufacture of cocainemanufacture of cocaine Can be mixed with tobacco and Can be mixed with tobacco and
smoked smoked
Cocaine hydrochloride Cocaine hydrochloride Most common form of pure Most common form of pure
cocainecocaine Stable water-soluble salt Stable water-soluble salt
© 2011 McGraw-Hill Higher Education. All rights reserved.
Forms of CocaineForms of Cocaine
FreebaseFreebase Prepared as a chemical Prepared as a chemical
base base Can be heated and the Can be heated and the
vapors inhaledvapors inhaled
Crack or rockCrack or rock Lumps of dried, Lumps of dried,
smokable cocainesmokable cocaine Prepared by mixing Prepared by mixing
cocaine with water and cocaine with water and baking sodabaking soda
© 2011 McGraw-Hill Higher Education. All rights reserved.
Contemporary Legal Contemporary Legal Controls on CocaineControls on Cocaine
Cocaine use began to increase again at the end Cocaine use began to increase again at the end of the 1960sof the 1960s
Prior to 1985, the major form of the drug available Prior to 1985, the major form of the drug available was cocaine hydrochloride, which was snortedwas cocaine hydrochloride, which was snorted Cocaine was relatively expensive and its use was Cocaine was relatively expensive and its use was
associated with status, wealth, and fameassociated with status, wealth, and fame
Then an inexpensive ($5 to $10 a hit) form of Then an inexpensive ($5 to $10 a hit) form of smokable cocaine became available—crack smokable cocaine became available—crack Smoked cocaine has a greater abuse potential than Smoked cocaine has a greater abuse potential than
snorted cocaine snorted cocaine
© 2011 McGraw-Hill Higher Education. All rights reserved.
Contemporary Legal Contemporary Legal Controls on CocaineControls on Cocaine
Media and politicians focused on crack use Media and politicians focused on crack use among urban blacksamong urban blacks Associated with violence and dependencyAssociated with violence and dependency
Anti-Drug Abuse Acts of 1986 and 1988Anti-Drug Abuse Acts of 1986 and 1988 Penalties for sale of crack cocaine significantly more Penalties for sale of crack cocaine significantly more
severe than penalties associated with powder cocainesevere than penalties associated with powder cocaine Tougher penalties for first-time users of crackTougher penalties for first-time users of crack
Concerns about federal cocaine sentencing policy Concerns about federal cocaine sentencing policy Does it overstate the seriousness of most crack Does it overstate the seriousness of most crack
cocaine offenses? cocaine offenses? Does it disproportionately affect the black community?Does it disproportionately affect the black community?
© 2011 McGraw-Hill Higher Education. All rights reserved.
Mechanism of ActionMechanism of Action
Chemical structure does not tell us how or why cocaine Chemical structure does not tell us how or why cocaine affects the brainaffects the brain
Cocaine blocks reuptake of dopamine, serotonin, and Cocaine blocks reuptake of dopamine, serotonin, and norepinephrine norepinephrine
© 2011 McGraw-Hill Higher Education. All rights reserved.
Cocaine AdministrationCocaine Administration
Chewing or sucking coca leavesChewing or sucking coca leaves Slow absorption and onset of effectsSlow absorption and onset of effects
““Snorting” through nasal mucous Snorting” through nasal mucous membranesmembranes Rapid absorption and onset of effectsRapid absorption and onset of effects
Injected intravenouslyInjected intravenously Rapid and brief effectsRapid and brief effects
SmokedSmoked Rapid and brief effectsRapid and brief effects
© 2011 McGraw-Hill Higher Education. All rights reserved.
Cocaine EliminationCocaine Elimination
Cocaine is metabolized by enzymes in the Cocaine is metabolized by enzymes in the blood and liverblood and liver
Cocaine has a half-life of about one hourCocaine has a half-life of about one hour Major metabolites (detected by drug Major metabolites (detected by drug
screens) have a half-life of eight hoursscreens) have a half-life of eight hours
© 2011 McGraw-Hill Higher Education. All rights reserved.
Potential Beneficial UsesPotential Beneficial Uses
Local anesthetic properties of cocaine were Local anesthetic properties of cocaine were discovered in 1860, but the drug was not discovered in 1860, but the drug was not used medically until 1884used medically until 1884
Synthesized drugs have largely replaced Synthesized drugs have largely replaced cocaine for medical usecocaine for medical use
Cocaine remains in use for surgery in the Cocaine remains in use for surgery in the nasal, laryngeal, and esophageal regionsnasal, laryngeal, and esophageal regions
© 2011 McGraw-Hill Higher Education. All rights reserved.
Causes for Concern: Causes for Concern: Acute ToxicityAcute Toxicity
Acute cocaine toxicity causes profound CNS Acute cocaine toxicity causes profound CNS stimulation, which can lead to respiratory or stimulation, which can lead to respiratory or cardiac arrestcardiac arrest
Significant individual variation in the uptake and Significant individual variation in the uptake and metabolism of cocainemetabolism of cocaine Difficult to estimate the size of a lethal doseDifficult to estimate the size of a lethal dose
Rare, severe, and unpredictable reactions can Rare, severe, and unpredictable reactions can cause cardiac failure cause cardiac failure
Cocaine combined with alcohol can cause the Cocaine combined with alcohol can cause the formation of the toxic chemical cocaethyleneformation of the toxic chemical cocaethylene
© 2011 McGraw-Hill Higher Education. All rights reserved.
Causes for Concern: Causes for Concern: Chronic ToxicityChronic Toxicity
Risks of regularly Risks of regularly snorting cocainesnorting cocaine Damage to the nasal Damage to the nasal
septumseptum Paranoid psychosisParanoid psychosis Damage to the heart Damage to the heart
musclemuscle
© 2011 McGraw-Hill Higher Education. All rights reserved.
Causes for Concern: Causes for Concern: Chronic ToxicityChronic Toxicity
DependenceDependence occurs in some users occurs in some users Animal and human studies have shown that Animal and human studies have shown that
cocaine is a cocaine is a powerfully reinforcingpowerfully reinforcing drugdrug Some people experience Some people experience withdrawal withdrawal
symptoms symptoms
© 2011 McGraw-Hill Higher Education. All rights reserved.
Causes for ConcernCauses for Concern
Cocaine use during Cocaine use during pregnancypregnancy Increased risk of Increased risk of
miscarriage and torn miscarriage and torn placentaplacenta
Long-term effects of Long-term effects of prenatal cocaine prenatal cocaine exposure still under exposure still under study study
Infant exposed to cocaine being monitored in ICU
© 2011 McGraw-Hill Higher Education. All rights reserved.
Supply of Illicit CocaineSupply of Illicit Cocaine
Readily available in all Readily available in all major U.S. citiesmajor U.S. cities
Street cocaine averages Street cocaine averages about 50-75 percent pureabout 50-75 percent pure
Most illicit cocaine comes Most illicit cocaine comes from Peru, Bolivia, and from Peru, Bolivia, and ColumbiaColumbia
Seized cocaine
© 2011 McGraw-Hill Higher Education. All rights reserved.
Cocaine: Current Use and Cocaine: Current Use and Future TrendsFuture Trends
2006 surveys indicate that about 2 percent 2006 surveys indicate that about 2 percent of adults currently use cocaineof adults currently use cocaine Down from a high of 7 to 9 percent in the 1980s Down from a high of 7 to 9 percent in the 1980s
Usage rates of cocaine and amphetamine Usage rates of cocaine and amphetamine tend to cycle in opposition to each othertend to cycle in opposition to each other
© 2011 McGraw-Hill Higher Education. All rights reserved.
Amphetamines: Amphetamines: HistoryHistory
The Chinese used a The Chinese used a medicinal tea made from medicinal tea made from ma huang (Ephedra)ma huang (Ephedra) Active ingredient = ephedrine Active ingredient = ephedrine
Ephedrine is a Ephedrine is a sympathomimetic drugsympathomimetic drug Stimulates the sympathetic Stimulates the sympathetic
branch of the autonomic branch of the autonomic nervous systemnervous system
© 2011 McGraw-Hill Higher Education. All rights reserved.
Amphetamines: Amphetamines: HistoryHistory
New synthesized chemical similar to ephedrine, New synthesized chemical similar to ephedrine, called amphetamine, was patented in 1932called amphetamine, was patented in 1932
Amphetamine was used medically Amphetamine was used medically Asthma Asthma NarcolepsyNarcolepsy Hyperactivity in childrenHyperactivity in children Appetite suppressant Appetite suppressant StimulantStimulant
© 2011 McGraw-Hill Higher Education. All rights reserved.
Amphetamines:Amphetamines:HistoryHistory
Use by soldiers in World War II to fight fatigueUse by soldiers in World War II to fight fatigue 1960s1960s
Amphetamine + heroin injected together = speedball Amphetamine + heroin injected together = speedball Most street amphetamines came from prescriptionsMost street amphetamines came from prescriptions ““Speed scene” = a time and place in which people used Speed scene” = a time and place in which people used
and became dependent on intravenous amphetamine and became dependent on intravenous amphetamine
Amphetamines became more tightly controlledAmphetamines became more tightly controlled Many look-alikes appearedMany look-alikes appeared Some users switched back to cocaineSome users switched back to cocaine Illicit manufacture of methamphetamine grewIllicit manufacture of methamphetamine grew
© 2011 McGraw-Hill Higher Education. All rights reserved.
Amphetamines:Amphetamines:HistoryHistory
Limited amphetamine Limited amphetamine availability increased availability increased the number of illicit the number of illicit laboratories making laboratories making methamphetaminemethamphetamine
Manufacture of Manufacture of methamphetamine is methamphetamine is dangerous and dangerous and associated with toxic associated with toxic fumes and residuefumes and residue Materials from a garage meth lab
© 2011 McGraw-Hill Higher Education. All rights reserved.
Amphetamines:Amphetamines:HistoryHistory
Methamphetamine Methamphetamine hydrochloride crystals hydrochloride crystals Ice or crystal methIce or crystal meth SmokableSmokable
Methamphetamine abuse Methamphetamine abuse began in the western began in the western United States and then United States and then spread east; it is also now spread east; it is also now considered a “club drug”considered a “club drug”
© 2011 McGraw-Hill Higher Education. All rights reserved.
AmphetamineAmphetaminePharmacologyPharmacology
Chemical structure of amphetamine is similar to Chemical structure of amphetamine is similar to the catecholamine neurotransmittersthe catecholamine neurotransmitters
The structure of methamphetamine allows it to The structure of methamphetamine allows it to more easily cross the blood-brain barriermore easily cross the blood-brain barrier Ephedrine and PPA are less able to cross the barrier Ephedrine and PPA are less able to cross the barrier
and so produce more peripheral than central nervous and so produce more peripheral than central nervous system effectssystem effects
Causes increased activity of monoamine Causes increased activity of monoamine neurotransmitters (dopamine, norepinephrine, neurotransmitters (dopamine, norepinephrine, serotonin) by stimulating their release serotonin) by stimulating their release
© 2011 McGraw-Hill Higher Education. All rights reserved.
Molecular StructureMolecular Structure
© 2011 McGraw-Hill Higher Education. All rights reserved.
Amphetamine Amphetamine Absorption and EliminationAbsorption and Elimination
Peak effects Peak effects 1.5 hours after oral ingestion1.5 hours after oral ingestion 5-20 minutes after intranasal administration 5-20 minutes after intranasal administration 5-10 minutes following intravenous injection or 5-10 minutes following intravenous injection or
smokingsmoking
Half-life Half-life 5-12 hours5-12 hours
Rapid tolerance (Rapid tolerance (tachyphylaxistachyphylaxis) can occur ) can occur after high dosesafter high doses
© 2011 McGraw-Hill Higher Education. All rights reserved.
Beneficial UsesBeneficial Uses
Previous use for depressionPrevious use for depression to temporarily elevate to temporarily elevate moodmood Adjunctive therapy- a treatment used together with primary Adjunctive therapy- a treatment used together with primary
treatment. treatment. The benefit of amphetamines is that their effects occur rapidly The benefit of amphetamines is that their effects occur rapidly
compared with standard antidepressant medications. compared with standard antidepressant medications.
© 2011 McGraw-Hill Higher Education. All rights reserved.
Beneficial UsesBeneficial Uses
Weight controlWeight control Widely use to reduce food intake and body Widely use to reduce food intake and body
weight weight Effect is real but small Effect is real but small Combination of fenfluramine and phentermine Combination of fenfluramine and phentermine
was associated with heart valve damage and was associated with heart valve damage and lung disease in some people lung disease in some people
© 2011 McGraw-Hill Higher Education. All rights reserved.
Beneficial UsesBeneficial Uses
NarcolepsyNarcolepsy (uncontrolled daytime episodes (uncontrolled daytime episodes of muscular weakness and falling asleep)of muscular weakness and falling asleep) Stimulants used to keep patients awake during Stimulants used to keep patients awake during
the daythe day Newer drug modafinil (Provigil) promotes Newer drug modafinil (Provigil) promotes
wakefulness by increasing the activity of wakefulness by increasing the activity of norepinephrine and dopaminenorepinephrine and dopamine Low abuse potential Low abuse potential Doesn’t induce toleranceDoesn’t induce tolerance
© 2011 McGraw-Hill Higher Education. All rights reserved.
Beneficial UsesBeneficial Uses
Treatment of attention-deficit Treatment of attention-deficit hyperactivity disorder (ADHD)hyperactivity disorder (ADHD) Characterized by problems with Characterized by problems with
inattention, hyperactivity, and inattention, hyperactivity, and impulsivityimpulsivity
Stimulant medications can reverse Stimulant medications can reverse catecholamine-associated deficits catecholamine-associated deficits that may underlie ADHDthat may underlie ADHD
Due to side effects and concerns Due to side effects and concerns about the risk of abuse, other about the risk of abuse, other treatments for ADHD are being treatments for ADHD are being studied studied
© 2011 McGraw-Hill Higher Education. All rights reserved.
Beneficial UsesBeneficial Uses
““Smart pills”Smart pills” At a low level of arousal, may improve At a low level of arousal, may improve
performanceperformance At a high level of arousal, may decrease At a high level of arousal, may decrease
performance, especially on complex or difficult performance, especially on complex or difficult tasks that require concentration tasks that require concentration
AthleticsAthletics Under some circumstances, may produce slight Under some circumstances, may produce slight
improvements in athletic performance improvements in athletic performance
© 2011 McGraw-Hill Higher Education. All rights reserved.
Effects of Stimulants on Effects of Stimulants on PerformancePerformance
© 2011 McGraw-Hill Higher Education. All rights reserved.
Acute ToxicityAcute Toxicity
Acute behavioral toxicity Acute behavioral toxicity Increases in feelings of power, suspicion, Increases in feelings of power, suspicion,
paranoiaparanoia Potential risk of violent behaviorPotential risk of violent behavior
Very high doses may destroy Very high doses may destroy catecholamine neuronscatecholamine neurons
Contaminants formed during the Contaminants formed during the manufacture of illicit methamphetamine manufacture of illicit methamphetamine may have toxic effects on brain cellsmay have toxic effects on brain cells
© 2011 McGraw-Hill Higher Education. All rights reserved.
Chronic Toxicity from Chronic Toxicity from High-Dose UseHigh-Dose Use
Paranoid psychosis Paranoid psychosis Two possible reasons for the psychosisTwo possible reasons for the psychosis
Heavy methamphetamine users have schizoid Heavy methamphetamine users have schizoid personalities. personalities.
Caused by sleep deprevation. Caused by sleep deprevation.
Higher risk among those who inject the drugHigher risk among those who inject the drug
© 2011 McGraw-Hill Higher Education. All rights reserved.
Dependence Potential ofDependence Potential ofAmphetaminesAmphetamines
Often no obvious withdrawal symptomsOften no obvious withdrawal symptoms Produce psychological dependence Produce psychological dependence Capable of producing dependence as Capable of producing dependence as
defined by DSM criteriadefined by DSM criteria A potent reinforcerA potent reinforcer
© 2011 McGraw-Hill Higher Education. All rights reserved.
Chapter 6Chapter 6
StimulantsStimulants