Uppers Downers & All Arounders

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Transcript Uppers Downers & All Arounders

Uppers Downers & All
Arounders
Chapter 2, Part II
Physiological Responses to Drugs
• Determines how drugs affect people and
why it is difficult to control their levels of
use.
• They include:
– Tolerance to Drug
– Tissue Dependence
– Psychological Dependence & Rewardreinforcing action of drugs
– Withdrawal
Tolerance
• Results from the body’s attempt to eliminate a
drug that it treats as a toxin
• With continued drug use the body tries to
neutralize the toxic effects by:
– Requiring larger amounts of the drugs to achieve the
original effects
• Degree of effects depend on the :
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Amount used
Duration of use
Frequency of use
Individual’s chemistry
State of mind
Kinds of Tolerance
• Dispositional Tolerance
– Speeds up the metabolism to handle the drug
in order to eliminate it
– Example: Increases the amount of cytocells
and mitochondria in the liver to neutralize the
drug….. So it will take more of the drug to
achieve the same level of intoxication
Kinds of Tolerance
• Pharmacodynamic Tolerance
– Results from the desensitization of nerve cells
to the action of the drug
– Ex. The nerve cells become less sensitive
and begin producing an antidote or antagonist
to the drug, ie. The brain will generate more
opiod receptor sites.
Kinds of Tolerance
• Behavioral Tolerance:
– Brain adjustments that affect behavior
– Someone who is high may make himself appear sober when
threatened, then revert back to the high state
• Reverse Tolerance
– Person has greater sensitivity to the drug, after prolong use, and
the body’s ability to metabolize the drug decreases.
– Ex. A person who has drunk a 12-pack of beer daily for ten
years, may find themselves drinking 3-4 beers to achieve the
effect due to tissue damage of the liver and kidneys.
– Also, the person may stay drunk longer as the liver is no longer
metabolizing the alcohol and the alcohol just continues to
circulate in the body until it is eliminated.
Kinds of Tolerance
• Acute Tolerance:
– The body’s immediate resistance to the effects of the
drug
– Ex. The brain and the body adapts instantly to the
drug, as with tobacco
• Select Tolerance:
– The body will develop a tolerance to some effects of
the drug, but not to other effects resulting in
potentially fatal side-effects in high doses of the drug.
– Ex: The body may not feel the euphoric effect, but
the organs of the body may react adversely to the
drug: respiratory function of the lungs and continue
damage to the liver
Kinds of Tolerance
• Inverse Tolerance (Kindling)
– Person becomes more sensitive to the drug
as the brain chemistry changes
– After months of using marijuana or cocaine
with minimal effect, the drug user may get an
intense effect/reaction
– Greater risk for heart attack or stroke
Development of Amphetamine
Tolerance Over Time
Desired effect
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• Tolerance develops rapidly to amphetamines. As the body adapts to
the toxin, the liver, brain, and other tissues become better able to
handle greater amounts. One dose of amphetamine on day 1 can
increase to 30 doses on day 100 to achieve the same effect.
Tolerance usually develops with higher-dose chronic use. Low-dose
infrequent use induces only minimal tolerance. (p.58)
Tissue Dependence
• Biological adaptation of the body to the
drug such that the body comes to depend
on the drug to stay in balance.
• The tissues and organs of the body come
to depend on the drug to stay functional
– Ex. Alcoholic will need a drink to ward off the
shakes
– Heroin addict will need a fix to stop body
aches, headaches
Psychological Dependence & the
Reward-reinforcing Action of the Drugs
• Results from the action of the drugs on the
brain chemistry
• Pleasurable effects induce user to
continual use
• Recognized as an important factor that
contributes to addiction
• Altered states of distorted perceptions of
pleasurable feelings prompt users to avoid
life’s problems
Withdrawal
• Marked by unpleasant effects that follow
the cessation of drug use as the body
attempts to restore its chemical balance
– Withdrawal can be so severe that the user will
continue to use drugs to avoid withdrawal
symptoms
• Kinds of Withdrawal
– Non-purposive Withdrawal
– Purposive
– Protracted Withdrawal
Kinds of Withdrawal
• Non-purposive:
– Series of unpleasant or even life-threatening
physiological effects that accompanies
cessation of use by an addict
– Example: Sweating, headaches, vomitting,
diarrhea, body aches, tremors,
• Purposive:
– Emotional expectation of physical effects
– Manipulative counterfeiting in an effort to
obtain more drugs, money or sympathy
Kinds of Withdrawal
• Protracted withdrawal (environmental
triggers and cues)
– Flashback or recurrence of addiction
withdrawal symptoms that trigger heavy
craving for a drug long after detoxification
– Cravings can be triggered by a sensation
associated with prior use and can be strong
enough to cause relapse
– PAWS (Post Acute Withdrawal Syndrome)
OPIOD EFFECTS VS WITHDRAWAL SYMPTOMS
EFFECTS
Withdrawal Symptoms
Numbness
Becomes painful
Euphoria
Anxiety, depression or craving
Dryness of mouth
Sweating, runny nose, tearing,
increased salivation
Constipation
Diarrhea
Slow pulse
Rapid pulse
Low blood pressure
High blood pressure
Shallow breathing ,
Suppressed cough
Coughing
Pinpoint pupils
Dilated pupils
Sluggishness
Severe hyper-reflexes,
muscle cramps
Basic Pharmacology
• Metabolism & Excretion
– Metabolism is the ability of the body to process, use
and inactivate drugs or food
– Chief organ of metabolism is the liver
– Metabolism rates vary depending on the age, gender,
race, heredity, general health, emotional state,
presence of other drugs, weight, tolerance and
exaggerated or allergic reactions
– Excretion is the process of elimination of those
substances from the body
– Chief organs of excretion are the kidneys via the
Urethra
• Other pathways of excretion is the sweat glands, & lungs
The liver is most responsible for metabolizing, detoxi-fying, and eliminating drugs. The drugladen blood enters through the portal vein, is processed by various enzymes, and then sent
via the hepatic vein to the heart where it is then pumped to the rest of the body. If the alcohol
and another depressant drug are taken together, they compete for the same enzymes so the
liver allows the other to enter the circulatory system at full strength.
The Liver
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Desired Effects vs Side Effects
• Desired Effects include:
– Satisfying curiosity, getting high, self-medicating,
gaining self confidence, increased energy, relieving
pain, controlling anxiety, peer pressure, social
confidence, boredom, altering consciousness, coping
with isolation, competion, seeking oblivion
• Side Effects: (Biopsychosocial)
– Mild to moderate to fatal effects
• Polydrug Use:
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Combination of more than one drug
May use another drug to replace the unavailable one
Get a different feeling
Enhance effects
Counteract effects
Cross addiction
LEVELS OF USE
Levels of Use
Abstention
Experimental
Social/Recreational
Habitual
Abuse
Addiction
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LEVELS OF USE
• Abstinence:
– Not using drugs, except accidentally
– With true abstinence, drug craving cannot develop not
matter how high hereditary and environmental
predisposition factors are
• Experimentation:
– Infrequent use of a drug to satisfy curiosity
– Only few exposures, no pattern of use develops
– Problematic consequences can occur if user is
pregnant, driving, has physical or mental illness, has
an alergic reaction or has legal problems
LEVELS OF USE
• Social/recreational Use
– Use has irregular pattern with small impact on
person’s life
– Same consequences of use can occur as with
experimentation
• Habituation:
– Regular pattern of use and loss of some control over
a drug with minimal harmful consequences
• Drug Abuse
– Continues to use despite negative consequences,
including health, school, work, emotional well-being
and drug use continues on a regular basis.
LEVELS OF USE
• Addiction/Dependency
– Difference between abuse and Addiction is the
Compulsion to use
– Uses drug in larger amounts or for longer periods of
time
– Unsuccessfully tries to cut down or control use
– Spends a great amount of time in activities to obtain
drugs or recover from use
– Gives up or reduces important social, occupational or
recreational activities because of use
– Continues use despite knowledge that drug use is
causing physical or psychological problems
Theories of Addiction
• DSM IV-TR divides substance related disorders
into substance use and substance induced
disorders
• Substance use disorders are divided into abuse
and dependency
• Substance-induced disorders include conditions
that are caused by specific substances,
intoxication, withdrawal, delirium, etc.
• Theories of Addiction focus on the environment,
the host (user) and agent (drug itself) and the
interactions between them
Theories of Addiction
• The Disease Model AKA Medical Model
– Addiction is a chronic, progressive, relapsing,
incurable and potentially fatal disease
– Triggered by drug use that reacts to
biochemical and neurological irregularities.
– Sees heredity as more important than
environmental influences in moving a person
to addiction
– Addiction is characterized by impulsive use,
loss of control, repeated attempts at
abstinence, continuation of use despite
negative consequences, and complications
resulting from abuse
Theories of Addiction
• The Behavioral/Environmental Model
– Sees addiction as environmental and developmental
influences as the main causes leading a person to
addiction.
– Stress, anger and peer pressure are some stress
factors
• Academic Model
– Sees addiction as occurring when body adapts to the
toxic effects of drugs.
– Given enough drugs over time, a person will become
addicted
– The process is characterized by tissue dependence,
withdrawal syndrome, and psychic dependence
Theories of Addiction
• Diathesis-Stress Theory of Addiction
– Result of genetic and environmental factors
such as stress
– People with a pre-disposition or vulnerability
to develop drug addiction is caused by:
• genetic and environment factors combined with an
• availability of drugs and
• practice of certain behaviors.
– When a person is stressed or challenged by
the use of drugs or behaviors, then the brain
changes to the point where return to normal
use or behavior is difficult
Heredity, Environment & Use of
Psychoactive Drugs
• Heredity:
– Many traits are passed on through generations
– Heredity susceptibility to avoid, use or abuse drugs
varies from person to person, depending on the brain
structure and neurochemical composition
– Twin Studies
– 34% with one parent, 400% 2 parents, 900% with
grandparents
– Alcoholic-Associated Genes
• DRD A1 Allele gene found in 70% of chronic alcoholics
• DRD4 gene with excessive dopamine prevents dependence
from developing
Heredity, Environment & Use of
Psychoactive Drugs
• Environmental factors include:
– Physical/sexual/emotional abuse
– Stress
– Nutrition
– Living conditions
– Family relationships
– Health care
– School quality
– Peer pressure
– Economic factor
Heredity, Environment & Use of
Psychoactive Drugs
• Psychoactive Drugs
– Move people further along the compulsion
curve
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Depends on strength of drug
Amount
Frequency and
Duration of use
– Long Term or heavy use may take a person
with low susceptibility 10 years of heavy
drinking to become an alcoholic
– A person with high susceptibility can take just
1 year to become an alcoholic
SPECT stands for single photon emission computerized tomography, a method for
imaging the activity of the brain. It shows areas of activity and inactivity. The “holes” in the
brain are actually areas that are inactivated by the use of a drug or the practice of some
behavior. Abstinence will restore much but not all of the brain function. The more chronic
the use, the less restoration of activity. Methamphetamine is more toxic than heroin or
cocaine.
Normal Brain
Methamphetamine Abuse
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Alcohol is a protoplasmic poison, so much of the inactivation in the
brain of a chronic alcoholic can be long lasting. Heroin is less toxic to
brain cells, so abstinence will restore more brain function
Chronic Alcohol Abuse
Heroin Abuse
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