2.  addiction – a state characterized by compulsive
engagement in rewarding stimuli, despite adverse
consequences
 reinforcing stimuli – stimuli that increase the probability
of repeating behaviors paired with them
 rewarding stimuli – stimuli that the brain interprets as
intrinsically positive or as something to be approached
 addictive drug – a drug that is both rewarding and
reinforcing
 addictive behavior – a behavior that is both rewarding and
reinforcing
 sensitization – an amplified response to a stimulus
resulting from repeated exposure to it

3.  drug tolerance – the diminishing effect of a drug
resulting from repeated administration at a given dose
 drug sensitization or reverse tolerance – the
escalating effect of a drug resulting from repeated
administration at a given dose
 drug dependence – an adaptive state associated with a
withdrawal syndrome upon cessation of repeated drug
intake
 physical dependence – dependence that involves
persistent physical–somatic withdrawal symptoms
(e.g., fatigue)
 psychological dependence – dependence that involves
emotional–motivational withdrawal symptoms

4. Drug dependence is the term which has
formally replaced addiction in medical terminology.
In 1964 the World Health Organization Expert
Committee on Drug Abuse proposed that the terms
addiction and habituation be replaced with the
term dependence and distinguished between two
types psychological dependence and physical
dependence.

5. Health Problems
 The impact of drug abuse and dependence can be far-
reaching, affecting almost every organ in the human body.
Drug use can:
 Weaken the immune system, increasing susceptibility to
infections.
 Cause cardiovascular conditions ranging from abnormal heart
rate to heart attacks. Injected drugs can also lead to collapsed
veins and infections of the blood vessels and heart valves.
 Cause nausea, vomiting and abdominal pain.
 Cause the liver to have to work harder, possibly causing
significant damage or liver failure.
 Cause seizures, stroke and widespread brain damage that can
impact all aspects of daily life by causing problems with
memory, attention and decision-making, including sustained
mental confusion and permanent brain damage.
 Produce global body changes such as breast development in
men, dramatic fluctuations in appetite and increases in body
temperature, which may impact a variety of health conditions

6. Effects On The Brain
 Although initial drug use may be voluntary, drugs have
been shown to alter brain chemistry, which interferes
with an individual's ability to make decisions and can
lead to compulsive craving, seeking and use. This then
becomes a substance dependency.
 All drugs of abuse - nicotine, cocaine, marijuana, and
others - effect the brain's "reward" circuit, which is part
of the limbic system.
 Drugs hijack this "reward" system, causing unusually
large amounts of dopamine to flood the system.
 This flood of dopamine is what causes the "high" or
euphoria associated with drug abuse.

7. Behavioral Problems
 Paranoia
 Aggressiveness
 Hallucinations
 Addiction
 Impaired Judgment
 Impulsiveness
 Loss of Self-Control

8. 2289 If morality requires respect for the life of the body,
it does not make it an absolute value. It rejects a neo-
pagan notion that tends to promote the cult of the
body, to sacrifice everything for it's sake, to idolize
physical perfection and success at sports. By its
selective preference of the strong over the weak, such a
conception can lead to the perversion of human
relationships.

9. 2290 The virtue of temperance disposes us to avoid
every kind of excess: the abuse of food, alcohol,
tobacco, or medicine. Those incur grave guilt who, by
drunkenness or a love of speed, endanger their own
and others' safety on the road, at sea, or in the air.
2291 The use of drugs inflicts very grave damage on
human health and life. Their use, except on strictly
therapeutic grounds, is a grave offense. Clandestine
production of and trafficking in drugs are scandalous
practices. They constitute direct co-operation in evil,
since they encourage people to practices gravely
contrary to the moral law.