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PSY 302: Substance Abuse Chapter 3: Depressants

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Page 1: PSY 302: Substance Abuse Chapter 3: Depressants. Depressants Drugs that depress the overall functioning of the Central Nervous System (CNS) to induce

PSY 302: Substance Abuse

Chapter 3: Depressants

Page 2: PSY 302: Substance Abuse Chapter 3: Depressants. Depressants Drugs that depress the overall functioning of the Central Nervous System (CNS) to induce

Depressants

Drugs that depress the overall functioning of the Central Nervous System (CNS) to induce sedation, muscle relaxation, and drowsinessReduce tension and inhibitionsMay affect judgment, motor activity, and

concentration Typically these drugs are addicting

Page 3: PSY 302: Substance Abuse Chapter 3: Depressants. Depressants Drugs that depress the overall functioning of the Central Nervous System (CNS) to induce

Depressants

Narcotics Natural opium derivatives Semisynthetic Synthetic

Sedative-Hypnotic Drugs Barbiturates

Methaqualone Benzodiazepines

Alcohol

Page 4: PSY 302: Substance Abuse Chapter 3: Depressants. Depressants Drugs that depress the overall functioning of the Central Nervous System (CNS) to induce

The brain produces peptides called endorphinsThree specific endorphins have characteristics of morphine (analgesics)Large amounts of these are released when experiencing stress or painWhen they reach their receptor sites in CNS, they relieve pain

Endorphin Receptor Phenomenon Athlete’s ability to overcome painTreating pain with acupuncture

Endorphins

Page 5: PSY 302: Substance Abuse Chapter 3: Depressants. Depressants Drugs that depress the overall functioning of the Central Nervous System (CNS) to induce

These receptor sites are programmed to receive endorphins Also receptive to external chemicals such as morphine

Endorphins

Page 6: PSY 302: Substance Abuse Chapter 3: Depressants. Depressants Drugs that depress the overall functioning of the Central Nervous System (CNS) to induce

Direct Reinforcing EffectEndorphins have their own reinforcing effects

Indirect Reinforcing Effect Endorphin synapses may contribute to certain kinds of reinforcement by inhibiting the release of GABA indirectly

Endorphins

Page 7: PSY 302: Substance Abuse Chapter 3: Depressants. Depressants Drugs that depress the overall functioning of the Central Nervous System (CNS) to induce

Ingestion of large amounts of heroin or some other opiate can lead to an endorphin deficiency

The external chemical binds to the receptor site and causing the brain to slow its natural opiate production

Leads to addiction

Endorphins

Page 8: PSY 302: Substance Abuse Chapter 3: Depressants. Depressants Drugs that depress the overall functioning of the Central Nervous System (CNS) to induce

The body reacts to stress by secreting two types of chemical messengers:Hormones in the bloodNeurotransmitters in the brain

Stress & Addiction

Page 9: PSY 302: Substance Abuse Chapter 3: Depressants. Depressants Drugs that depress the overall functioning of the Central Nervous System (CNS) to induce

The body reacts to stress by secreting two types of chemical messengers:Hormones in the bloodNeurotransmitters in the brain

Depressants such as heroin inhibit the release of stress hormones and stress-related neurotransmittersHowever, most who are prescribed opiates for acute pain do not become addicted

Stress & Addiction

Page 10: PSY 302: Substance Abuse Chapter 3: Depressants. Depressants Drugs that depress the overall functioning of the Central Nervous System (CNS) to induce

A person having difficulties with stress who is exposed to opiates is likely to find them rewarding and become dependent on them

However, in the absence of stress, most people take opiates over long periods of time without becoming addicted Melzack (1990)

Only 2 of 38 chronic pain patients became addicted Over 10,000 burn victims treated with narcotics; none

became addicted

Stress & Addiction

Page 11: PSY 302: Substance Abuse Chapter 3: Depressants. Depressants Drugs that depress the overall functioning of the Central Nervous System (CNS) to induce

When stress is relatively low:Drug addicts trying to remain off drugs can usually resist cravings from environmental cues when stress levels are low

When stress is relatively high:Can lead to a sudden relapse

Stress & Addiction

Page 12: PSY 302: Substance Abuse Chapter 3: Depressants. Depressants Drugs that depress the overall functioning of the Central Nervous System (CNS) to induce

Hypersensitivity to stress may have existed before drug use, caused by the drug use, or exacerbated by the drug useChronic use of heroin may increase this hypersensitivity to stress and trigger a cycle of continued drug use when the heroin wears off

Since effects of heroin last only about 6 hours, addicts often experience withdrawal several times a day

Stress & Addiction

Page 13: PSY 302: Substance Abuse Chapter 3: Depressants. Depressants Drugs that depress the overall functioning of the Central Nervous System (CNS) to induce

Opioids

Derived from opium these drugs depress CNS functioning

Include: opium, morphine, codeine, and heroin Have the effect of dulling or numbing the

senses… Pupils constrict Breathing slows User becomes lethargic

For a few hours, such things as pain and anxiety are replaced by blissful pleasure

Page 14: PSY 302: Substance Abuse Chapter 3: Depressants. Depressants Drugs that depress the overall functioning of the Central Nervous System (CNS) to induce

But for bliss you pay the price…

Unfortunately, the bliss is eventually replaced by a gnawing craving for another fix

The path to addiction is insidious…When repeatedly flooded with these artificial

opiates – the brain stops producing its own natural opiates (endorphins)

So, when the drug is withdrawn, the brain lacks the normal level of these painkilling neurotransmitters

The result is the raw agony of withdrawal

Page 15: PSY 302: Substance Abuse Chapter 3: Depressants. Depressants Drugs that depress the overall functioning of the Central Nervous System (CNS) to induce

Its effects…

The effects of opiates, like those of other intoxicants, depend on:The user's state of mind and on the company

the user is inWhether an opiate is used on its own or

together with other intoxicantsWhether the user is a novice or an

experienced user also has an influence on the effects of the drug

Page 16: PSY 302: Substance Abuse Chapter 3: Depressants. Depressants Drugs that depress the overall functioning of the Central Nervous System (CNS) to induce

Heroin Heroin is a narcotic that is highly

addictive; It is processed from morphine, a naturally occurring substance extracted from the seedpod of the Asian poppy plant.

The most abused and most rapidly acting of the opiates.

Usually seen as a white or brown powder or as a black sticky substance. The differences in color are due to impurities left from the manufacturing process or the presence of additives.

Page 17: PSY 302: Substance Abuse Chapter 3: Depressants. Depressants Drugs that depress the overall functioning of the Central Nervous System (CNS) to induce

Heroin

Pure heroin, which is a white powder with a bitter taste, is rarely sold on the streets

Sometimes cut with other substances such as sugar, powdered milk, cornstarch, or even poisons like strychnine

Page 18: PSY 302: Substance Abuse Chapter 3: Depressants. Depressants Drugs that depress the overall functioning of the Central Nervous System (CNS) to induce

Methods of Use…

In the past heroin was mostly injected but in recent years it has been made in forms that can be smoked or snorted

The user feels the effect of heroin within seconds of taking it

Heroin is converted into morphine when it enters the brain, which disrupts normal brain activity and creates intense feelings of pleasure

Page 19: PSY 302: Substance Abuse Chapter 3: Depressants. Depressants Drugs that depress the overall functioning of the Central Nervous System (CNS) to induce

Effects of Heroin

IntravenousOnset: 10 seconds

SubcutaneousOnset: 5-8 minutes

Page 20: PSY 302: Substance Abuse Chapter 3: Depressants. Depressants Drugs that depress the overall functioning of the Central Nervous System (CNS) to induce

Short Term Reactions

Euphoria Warm flushing of the skin Dry mouth Heavy extremities Decreased mental ability Insensitivity to pain Vomiting Lowered breathing Lowered heart rate DEATH

Page 21: PSY 302: Substance Abuse Chapter 3: Depressants. Depressants Drugs that depress the overall functioning of the Central Nervous System (CNS) to induce

Long Term Reactions

Addiction High degree of tolerance Brain damage Arthritis Liver disease Infection of the heart lining HIV/AIDS or hepatitis Abscesses of the skin (at injection sites) DEATH

Page 22: PSY 302: Substance Abuse Chapter 3: Depressants. Depressants Drugs that depress the overall functioning of the Central Nervous System (CNS) to induce

Effects of Heroin

Agar (1973) The Rush The High The Nod Being Straight

Page 23: PSY 302: Substance Abuse Chapter 3: Depressants. Depressants Drugs that depress the overall functioning of the Central Nervous System (CNS) to induce

Tolerance for Heroin

Tolerance to the high and the nod require an increase in the dosage in order to gain the same level of responseMaintenance doses of morphine or some other narcotic can prevent physical withdrawal

Page 24: PSY 302: Substance Abuse Chapter 3: Depressants. Depressants Drugs that depress the overall functioning of the Central Nervous System (CNS) to induce

Heroin Withdrawal

Heroin causes severe physical and psychological symptoms 6 to 8 hours after the last dosage. Painful withdrawal gets worse as time passesSymptoms Include:

Runny nose muscle and bone pain Emotional distress and restlessness Diarrhea Vomiting Hot flashes and heavy sweating Cold flashes with goose bumps Insomnia An overwhelming need for more heroin

Page 25: PSY 302: Substance Abuse Chapter 3: Depressants. Depressants Drugs that depress the overall functioning of the Central Nervous System (CNS) to induce

Medical Use

Once used to control pain, it is no longer legal to use under any circumstance

Page 26: PSY 302: Substance Abuse Chapter 3: Depressants. Depressants Drugs that depress the overall functioning of the Central Nervous System (CNS) to induce

Abuse of Prescription Opioids

The main prescription opioids people abuse are Codeine Oxycodone (OxyContin®, Percodan®,

Percocet®) Hydrocodone (Vicodin®) Meperidine (Demerol®) Hydromorphone (Dilaudid®)

Page 27: PSY 302: Substance Abuse Chapter 3: Depressants. Depressants Drugs that depress the overall functioning of the Central Nervous System (CNS) to induce

OxycodoneUse Patterns

The number of people abusing oxycodone has increased every year since the drug was introduced in 1995

Page 28: PSY 302: Substance Abuse Chapter 3: Depressants. Depressants Drugs that depress the overall functioning of the Central Nervous System (CNS) to induce

OxycodoneFacts Oxycodone is timed-release medicine for cancer and back pain

People forge prescriptions and rob pharmacies to obtain oxycodone illegally

People abuse oxycodone by crushing the tablet and swallowing or snorting it or dissolving it in water

Page 29: PSY 302: Substance Abuse Chapter 3: Depressants. Depressants Drugs that depress the overall functioning of the Central Nervous System (CNS) to induce

OxycodoneDangers

When people crush tablets before taking them, the danger of overdose is increased.

Like all opioids, oxycodone is highly addictive when it is abused

Page 30: PSY 302: Substance Abuse Chapter 3: Depressants. Depressants Drugs that depress the overall functioning of the Central Nervous System (CNS) to induce

Sedative-Hypnotic Drugs: Barbiturates

Barbiturates are powerful depressants that slow down the central nervous system Classified as sedative/hypnotics

Once a very commonly used tranquilizer but because they are highly habit-forming their usage decreased They have effects similar to alcohol They depress sympathetic nervous system activity They have been used to induce sleep and reduce anxiety

In large doses, can lead to impaired memory and judgment

Page 31: PSY 302: Substance Abuse Chapter 3: Depressants. Depressants Drugs that depress the overall functioning of the Central Nervous System (CNS) to induce

Barbiturates

What it feels like… Relaxation, peacefulness, sleepiness, pleasurable

intoxication, dizziness, inactivity, withdrawal, interrupted thought processes, mood swing, excitement, increased pain, hostility, depression, anxiety, confusion, changed vision, intense emotions, hangover

Barbituates give a quick “high” but the effects drop off and persist for a low level for a longer duration

Page 32: PSY 302: Substance Abuse Chapter 3: Depressants. Depressants Drugs that depress the overall functioning of the Central Nervous System (CNS) to induce

Barbiturates: Tolerance

Acute tolerance develops virtually right away Chronic tolerance seems first to develop to

the depressant effects Next to the antianxiety effects Cross tolerance within benzodiazepines Some cross tolerance to barbiturates and

alcohol

Page 33: PSY 302: Substance Abuse Chapter 3: Depressants. Depressants Drugs that depress the overall functioning of the Central Nervous System (CNS) to induce

Barbiturates: Tolerance

As tolerance develops, users progressively increase their daily dose to many times the original

It is extremely important to note that in spite of acquiring tolerance to the intoxicating effects of barbiturates, the user develops no tolerance to the lethal action of the drug

Therefore, high doses could produce fatal results even for tolerant abusers.

High risk for fatal overdose

Page 34: PSY 302: Substance Abuse Chapter 3: Depressants. Depressants Drugs that depress the overall functioning of the Central Nervous System (CNS) to induce

Withdrawal

BarbituratesREM ReboundTremors InsomniaNauseaSeizuresHallucinations

Page 35: PSY 302: Substance Abuse Chapter 3: Depressants. Depressants Drugs that depress the overall functioning of the Central Nervous System (CNS) to induce

Medical Use

Used as sedatives for treatment of insomnia and as anticonvulsants to help prevent or mitigate epileptic seizuresNot used as much anymore; high risks

involved

Page 36: PSY 302: Substance Abuse Chapter 3: Depressants. Depressants Drugs that depress the overall functioning of the Central Nervous System (CNS) to induce

Sedative-Hypnotic Drugs: Benzodiazepines

Benzodiazepines (commonly referred to as benzos) are a more recent generation of tranquilizers

Some of the more common benzodiazepines are: ativan, librium, valium, and xanax

Potentially addictive Little risk of overdose

Page 37: PSY 302: Substance Abuse Chapter 3: Depressants. Depressants Drugs that depress the overall functioning of the Central Nervous System (CNS) to induce

Short-Term Effects

Relaxation Drowsiness Dizziness Confusion Mood swings

Page 38: PSY 302: Substance Abuse Chapter 3: Depressants. Depressants Drugs that depress the overall functioning of the Central Nervous System (CNS) to induce

Common Long-term Effects

Lethargy Irritability Nausea Loss of sexual interest Increased appetite Increased weight

Page 39: PSY 302: Substance Abuse Chapter 3: Depressants. Depressants Drugs that depress the overall functioning of the Central Nervous System (CNS) to induce

Withdrawal

BenzodiazepinesAgitationDepressionPainDTsREM rebound

Page 40: PSY 302: Substance Abuse Chapter 3: Depressants. Depressants Drugs that depress the overall functioning of the Central Nervous System (CNS) to induce

Medical Use

They are usually prescribed by doctors to treat anxiety and sleep problems, they can also, be used to treat panic disorders and muscle spasms, and occasionally used in the treatment of epilepsy and alcohol withdrawal (under strict medical supervision only)

Page 41: PSY 302: Substance Abuse Chapter 3: Depressants. Depressants Drugs that depress the overall functioning of the Central Nervous System (CNS) to induce

Abusers

Barbituates and benzodiapines are abused by two groups of people… Individuals who overuse these drugs to

reduce daily tensions and to aid in sleep These people take excessively large doses on a

regular basisStreet drug users

Attempt to achieve a state of “relaxed euphoria” or to aid in “coming down” from a high caused by taking a stimulant

Page 42: PSY 302: Substance Abuse Chapter 3: Depressants. Depressants Drugs that depress the overall functioning of the Central Nervous System (CNS) to induce

Methaqualone

Brand Name: Quaaludes/Ludes

Street Names: Ludes, Qualudes, Vitamin Q, The Love Drug, Wallbangers

Page 43: PSY 302: Substance Abuse Chapter 3: Depressants. Depressants Drugs that depress the overall functioning of the Central Nervous System (CNS) to induce

Side Effects

Methaqualone can be very addictive. Habitual users often grow physically and psychologically dependent on the drug.

Withdrawal symptoms can include restlessness, irritability, antisocial behavior, and insomnia.

More severe withdrawal cases may lead to delirium, nightmares, hallucinations, epileptic-like seizures that can lead to death, and severe cravings for the drug for long periods after withdrawal.

High risk for overdose

Page 44: PSY 302: Substance Abuse Chapter 3: Depressants. Depressants Drugs that depress the overall functioning of the Central Nervous System (CNS) to induce

Alcohol

Alcohol is a depressant yet we often feel lively after a couple of drinks… It gives this feeling by slowing down the brain

centers that control judgments and inhibitions

Page 45: PSY 302: Substance Abuse Chapter 3: Depressants. Depressants Drugs that depress the overall functioning of the Central Nervous System (CNS) to induce

Curious Effects

MemoryBlackouts

SexMale arousal and performance issues

Page 46: PSY 302: Substance Abuse Chapter 3: Depressants. Depressants Drugs that depress the overall functioning of the Central Nervous System (CNS) to induce

Blood Alcohol Level (BAL)

The amount of alcohol in your bloodSee next two slides for BAL of males and

females

Page 47: PSY 302: Substance Abuse Chapter 3: Depressants. Depressants Drugs that depress the overall functioning of the Central Nervous System (CNS) to induce
Page 48: PSY 302: Substance Abuse Chapter 3: Depressants. Depressants Drugs that depress the overall functioning of the Central Nervous System (CNS) to induce
Page 49: PSY 302: Substance Abuse Chapter 3: Depressants. Depressants Drugs that depress the overall functioning of the Central Nervous System (CNS) to induce

Genetic Influence

Six genes have been linked to addiction These genes seem to be linked primarily

to early-onset alcoholism

See next slide

Page 50: PSY 302: Substance Abuse Chapter 3: Depressants. Depressants Drugs that depress the overall functioning of the Central Nervous System (CNS) to induce

The genetic basis for early-onset alcoholism is stronger than for later-onset, especially in men

Researchers distinguish between two types of alcoholism Type I/Type A Type II/Type B

Genetic Influence

Page 51: PSY 302: Substance Abuse Chapter 3: Depressants. Depressants Drugs that depress the overall functioning of the Central Nervous System (CNS) to induce

Type I/Type A characteristics include:◦ Later onset◦ Gradual onset◦ Fewer genetic relatives with alcoholism◦ Equal quantity between men and women◦ Less severe

Genetic Influence

Page 52: PSY 302: Substance Abuse Chapter 3: Depressants. Depressants Drugs that depress the overall functioning of the Central Nervous System (CNS) to induce

Type II/Type B characteristic include:◦ Earlier onset (usually before 25)◦ More rapid onset◦ More genetic relatives with alcoholism◦ Men outnumber women◦ Often severe◦ Often associated with criminality

Genetic Influence

Page 53: PSY 302: Substance Abuse Chapter 3: Depressants. Depressants Drugs that depress the overall functioning of the Central Nervous System (CNS) to induce

Several studies have looked at the behaviors of sons of alcoholic fathers

ProcedureControl group would be males without alcoholic fathers

ResultsSons of alcoholics show less intoxication after drinking moderate amounts of alcoholLow initial response leads to greater drinking later in lifeMore of stress reliever for sons of alcoholicsBrain abnormalities (small amygdala) in sons of alcoholics (before they became alcohol abusers)

Genetic Influence

Page 54: PSY 302: Substance Abuse Chapter 3: Depressants. Depressants Drugs that depress the overall functioning of the Central Nervous System (CNS) to induce

AddictionGenes influence the likelihood of alcoholism in various ways:◦ Sensitivity of Dopamine type 4 receptor◦ Control of COMT enzyme that breaks down

dopamine

Genetic Influence

Page 55: PSY 302: Substance Abuse Chapter 3: Depressants. Depressants Drugs that depress the overall functioning of the Central Nervous System (CNS) to induce

Genetic Influence

Children of alcoholics are at 2- to 4-fold higher risk for developing alcohol problems.

About 50% of brothers and 25% sisters of an alcoholic are also alcoholic.

Yet, most individuals in a family are not affected with alcoholism.

Page 56: PSY 302: Substance Abuse Chapter 3: Depressants. Depressants Drugs that depress the overall functioning of the Central Nervous System (CNS) to induce

DSM Alcohol Withdrawal Criteria

A. Cessation of (or reduction in) alcohol use that has been heavy and prolonged.B. Two (or more) of the following, developing within several hours to a few days

after Criterion A. 1. Autonomic hyperactivity (e.g., diaphoresis or HR>100) 2. Increased hand tremor 3. Insomnia 4. Nausea and vomiting 5. Transient visual, tactile, or auditory hallucinations or illusions 6. Psychomotor agitation 7. Anxiety 8. Grand mal seizures

Page 57: PSY 302: Substance Abuse Chapter 3: Depressants. Depressants Drugs that depress the overall functioning of the Central Nervous System (CNS) to induce

DSM Alcohol Withdrawal Criteria

C. The symptoms in Criterion B cause clinically significant distress or impairment in functioning.

D. The symptoms are not due to a general medical condition and are not better accounted for by another mental disorder.

Page 58: PSY 302: Substance Abuse Chapter 3: Depressants. Depressants Drugs that depress the overall functioning of the Central Nervous System (CNS) to induce

Dangers of Alcohol Use

Wernicke–Korsakoff SyndromeUp to 80 percent of alcoholics have a deficiency in thiamine and some of these people will go on to develop serious brain disordersThe symptoms of Wernicke’s encephalopathy include mental confusion, paralysis of the nerves that move the eyes, and difficulty with muscle coordinationFor example, patients may be too confused to find their way out of a room or may not even be able to walk

Page 59: PSY 302: Substance Abuse Chapter 3: Depressants. Depressants Drugs that depress the overall functioning of the Central Nervous System (CNS) to induce

Dangers of Alcohol Use

Liver & Brain DiseaseMost people realize that heavy, long-term drinking can damage the liver, the organ chiefly responsible for breaking down alcohol into harmless byproducts and clearing it from the bodyBut people may not be aware that prolonged liver dysfunction, such as liver cirrhosis resulting from excessive alcohol consumption, can harm the brain, leading to a serious and potentially fatal brain disorder known as hepatic encephalopathy

Page 60: PSY 302: Substance Abuse Chapter 3: Depressants. Depressants Drugs that depress the overall functioning of the Central Nervous System (CNS) to induce

Dangers of Alcohol Use

Fetal Alcohol Syndrome (FAS)FAS is a lifelong yet completely preventable set of physical, mental and neurobehavioral birth defects associated with alcohol consumption during pregnancy

Alcohol enters the mother’s and the fetus’ bloodstreamFAS is the leading known cause of mental retardation and birth defects

Small disproportioned head and lifelong brain abnormalities

Page 61: PSY 302: Substance Abuse Chapter 3: Depressants. Depressants Drugs that depress the overall functioning of the Central Nervous System (CNS) to induce

How does a mother’s drinking affect her unborn child? Facts:

Through the blood vessels in the placenta, the mother’s blood supplies the developing baby with nourishment and oxygen

If the mother drinks alcohol, the alcohol enters her blood stream and then, through the placenta, enters the blood supply of the growing baby

So, when a pregnant woman drinks alcohol, so does her baby

Alcohol is a teratogen, a substance known to be toxic to human development

Page 62: PSY 302: Substance Abuse Chapter 3: Depressants. Depressants Drugs that depress the overall functioning of the Central Nervous System (CNS) to induce

Fetal Alcohol Syndrome (FAS)

Prenatal alcohol exposure does not always result in FAS—although there is no known safe level of alcohol consumption during pregnancy

Most individuals affected by alcohol exposure before birth do not have the characteristic facial abnormalities and growth retardation identified with FAS, yet they have brain and other impairments that are just as significant

Page 63: PSY 302: Substance Abuse Chapter 3: Depressants. Depressants Drugs that depress the overall functioning of the Central Nervous System (CNS) to induce

Sad facts…

In addition to mental retardation, individuals with FAS may have other neurological deficits such as poor motor skills and hand-eye coordination

They may also have a complex pattern of behavioral and learning problems, including difficulties with memory, attention and judgment.

As many as 12,000 infants are born each year with FAS

Page 64: PSY 302: Substance Abuse Chapter 3: Depressants. Depressants Drugs that depress the overall functioning of the Central Nervous System (CNS) to induce

Rohypnol

Benzodiazepine drug that is not legal in US but prescribed in other countries

Dangerous when mixed with alcohol as intoxication effects may be extreme

Severely impaired judgment and motor skills Complete blackouts are possible Long recovery period Prolonged use results in physical dependence

Page 65: PSY 302: Substance Abuse Chapter 3: Depressants. Depressants Drugs that depress the overall functioning of the Central Nervous System (CNS) to induce

Credits:

Some slides prepared with the help of the following websites: http://pubs.niaaa.nih.gov/publications/aa63/aa63.pdf www.towson.edu/atod/education/documents/Heroin_000.pptx http://www.midlandstech.edu/sbs/gummowa/psy212ch12.ppt.