This document discusses psychoactive drugs and their effects. It defines psychoactive drugs as those that affect the brain and alter consciousness. It describes how these drugs work in the brain by crossing the blood-brain barrier and interacting with neurotransmitters. It then discusses different types of drug effects including dependence, and provides examples of commonly abused drugs like cannabis, depressants, dissociatives, hallucinogens, opioids, and stimulants.

1. Psychoactive Drugs
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2. Psychoactive Drugs
 Drugs that affect the brain, changing
consciousness and other psychological
processes, are called psychoactive
drugs.
– 80-90% of adults in North America use some
kind of drug on a daily basis.
 The study of psychoactive drugs is called
psychopharmacology.

3. Psychopharmacology
 To affect the brain, a substance must
cross the blood-brain barrier.
 Then the substance’s effect depends on a
number of factors:
– Which neurotransmitter is targeted?
– How does the drug affect the
neurotransmitter or its receptors?
– What psychological functions are performed
by the brain systems which use that
neurotransmitter.

4. Psychopharmacology
 Agonist
molecules mimic
a
neurotransmitter
 Antagonist
molecules just
block a receptor
site.

5. Dependence
 Substance abuse may lead to psychological or
physical dependence.
– Psychological dependence: person continues use
despite adverse effects, needs the substance for a
sense of well-being, and becomes preoccupied.
– Physical dependence: physiological state in which
drug use is needed to prevent a withdrawal
syndrome.
 Tolerance is when a larger dose is required to produce
a similar effect as before.
– Habit-forming: a person continues substance use
out of sheer habit.

6. Commonly Abused
Drugs
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7.  Cannabinoids
– e.g. hashish & marijuana
– Euphoria; slowed thinking and reaction time;
confusion; impaired balance and coordination;
coughing or respiratory problems; impaired
memory or learning; increased heart rate or
anxiety; panic attacks

8.  Depressants
– e.g. Barbituates; benzodiazepines (eg
Valium); flunitrazepam (eg Rohypnol); GHB;
methaqualone; alcohol.
– Reduced pain and anxiety; feeling of well-
being; lowered inhibitions; slowed pulse &
breathing; lowered blood-pressure; poor
concentration/ confusion or fatigue; impaired
coordination, memory or judgment;
respiratory depression or arrest.

9.  Dissociative Anesthetics
– e.g. Ketamine; PCP
– Increased heart rate & blood pressure;
impaired motor function; memory loss;
numbness; nausea/ vomiting
 For ketamine: delirium; respiratory depression &
arrest
 For PCP: panic; aggression/ violence; loss of
appetite.

10.  Hallucinogens
– e.g. LSD; mescaline; psilocybin.
– Altered states of perception & feeling;
nausea; chronic mental disorders (persisting
perception disorder)
 For LSD & mescaline: increased body temperature;
insomnia; weakness; tremors.
 For psilocybin: nervousness; paranoia.

11.  Opinoids and Morphine derivatives
– e.g. codeine; fentanyl; heroin; morphine;
opium; OxyContin.
– Pain relief; euphoria; drowsiness; respiratory
depression & arrest; nausea; confusion;
constipation; sedation (unconsciousness,
coma)
 For heroin: staggering gait.

12.  Stimulants
– e.g. amphetamine; cocaine; MDMA;
methamphetamine; methylphenidate (Ritalin);
nicotine; caffeine.
– Increased heart rate, blood pressure &
metabolism; feelings of exhilaration, increased
mental alertness; rapid/irregular heart beat;
reduced appetite; irritability/ anxiousness.

13. Spiders on Drugs
A normal orb web On chloral hydrate
On benzadrine On caffeine

14. How do I know if I am abusing a
substance?
 increased frequency of use
 loss of control over frequency, duration and/or amount
of use
 drinking or using when you don't intend to
 substance use interferes with life activities (i.e. school,
relationships with family and friends)
 increased spending money on substance of choice
 personality changes noted by self and others
 getting into risky/dangerous behaviors
 other people express concern about your use/ your
behavior
 grades dropping
 missing classes and appointments
 legal trouble (i.e., DUI)

15. DSM IV: Addiction
 Substance is often taken in larger amounts or over longer period than
intended
 Persistent desire or unsuccessful efforts to cut down or control substance
use
 A great deal of time is spent in activities necessary to obtain the substance
(e.g., visiting multiple doctors or driving long distances), use the
substance (e.g., chain smoking), or recover from its effects
 Important social, occupational, or recreational activities given up or
reduced because of substance abuse
 Continued substance use despite knowledge of having a persistent or
recurrent psychological, or physical problem that is caused or exacerbated
by use of the substance
 Tolerance, as defined by either:
– need for read amounts of the substance in order to achieve intoxication or
desired effect; or
– markedly diminished effect with continued use of the same amount
 Withdrawal, as manifested by either:
– characteristic withdrawal syndrome for the substance; or
– the same (or closely related) substance is taken to relieve or avoid withdrawal
symptoms

16. When substance abuse becomes
severe …
 loss of friends (except perhaps other substance abusers)
 negative changes in appetite with possible weight loss
 possible reduction or loss of libido … and/or only able to
perform when using
 extreme mood swings, including anger and depression
 obsessions about using or procuring substance when not
under the influence
 lying about substance to use to friends and loved ones
 loss of memory for times when under the influence
 uncomfortable withdrawal symptoms when not using
 involvement in crime to support habit
 loss of energy and general health
 you are increasingly unable to believe your own denial and
excuses

17. How can psychological therapy
help?
 help clarify your pattern of abuse
 identify how your life has been affected
 help create strategies to decrease your
use
 identify related issues that may contribute
to your abuse
 if necessary, referral to more intensive
treatment resource