Transcript stimulants

Stimulants
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Stimulants
Stimulants are chemical substances that
enhance the activity of the brain and the central
nervous system.
They cause increased alertness and
wakefulness. In many cases they also act to
decrease appetite.
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Sympathomimetic Drugs
Sympathomimetic drugs are chemical
substances that mimic the effects of the
hormone, adrenalin.
Generally they cause constriction of the
arteries and increase metabolism.
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Neurotransmitters
L dopamine
Neurotransmitters work
to transmit electrical
neuro-impulses across
a synapse.
Many stimulants
enhance the neuroimpulse transmission
systems.
Serotonin
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The structures of
Stimulants
L Dopamine
many stimulants
mimic chemical
structures and are
closely related to the
neurotransmitters
found in the body.
Serotonin
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Amphetamines-Historical
Development
Amphetamines were initially developed as a
cure-all for helping long haul truckers stay
awake
They were also used for weight control, to
help athletes to perform better and train
longer
As amphetamine abuse became more
common, it became evident that the dangers
of abuse far outweighed therapeutic uses.
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Amphetamines
Amphetamine was first marketed in the
1930s as Benzedrine, an over-thecounter inhaler to treat nasal congestion.
It was also used in the treatment of the
sleeping disorder, narcolepsy, and the
behavioral syndrome called minimal
brain dysfunction (MBD), which today is
called attention deficit hyperactivity
disorder (ADHD).
During World War II, amphetamines were
used to keep the fighting men going
especially under intense battle
conditions.
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Amphetamines
Amphetamines
closely mimic the
chemical structure
of adrenalin.
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Amphetamines
Amphetamines act by
constricting arteries, increasing perspiration
activity and stimulating brain activity.
increasing heart rate and blood pressure,
increasing wakefulness, restlessness,
agitation and insomnia.
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Amphetamines --Harmful Effects
highly addictive and toxic
Long term use leads to deterioration of a
number of body systems.
Chronic abuse produces a psychosis that
resembles schizophrenia and is characterized
by paranoia, picking at the skin,
preoccupation with one's own thoughts, and
auditory and visual hallucinations.
Severe depression and violent or erratic
behavior are also common among meth
addicts.
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Ecstasy
Ecstasy is a powerful
stimulant that has
some characteristics
in common with
adrenalin and Ldopamine as well.
Repeated use of Ecstasy ultimately may damage the
cells that produce serotonin, which has an important
role in the regulation of mood, appetite, pain, learning
and memory.
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Ecstasy - Effects
Attempts to synthesize new
amphetamines led to so
called designer drugs, all of
which are highly dangerous.
Because it mimics LDopamine, it has been
used to relieve
symptoms of
Parkinson’s Disease.
Results in mental
relaxation, increased
sensitivity to stimuli and
hallucinations.
It can be produce fatal
effects even from a
single exposure
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Nicotine
Nicotine is an
alkaloid found in
the nightshade
family of plants
(Solanaceae)
It constitutes
approximately 0.6–
3.0% of dry weight
of tobacco
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Nicotine -Short Term
Sympathomimetic
Increases
concentration and
relieves tension
Increased heart
rate
Increased blood
pressure
Reduction in urine
output
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Nicotine – Long Term
Highly addictive
Increased risk of
heart disease and
coronary thrombosis
Increased stomach
acid and risk of
peptic ulcers
Chronic lung
disease
Increased risk of
cancer
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Nicotine -- Addiction and
Withdrawal
Cessation of
smoking difficult
Cravings
Nausea, weight
gain, insomnia,
irritability, and
depression
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Caffeine Characteristics
Alkaloid
Widely used stimulant
found in coffee and
tea.
Added to some pain
killers to speed up
their effects.
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Caffeine Effects
Increases alertness,
concentration, and
restlessness
Diuretic
Potential
dependence
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Theobromine
Theobromine
Caffeine
Found in chocolate
Effects similar to
caffeine.
Structure is similar
to that of caffeine
but the methyl
group on the
nitrogen between
the two carbonyl
groups is missing
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Theobromine
Theobromine
Theobromine has a bitter
flavor, which gives dark
chocolate its typical bitter
taste.
Although theobromine
does not cause harmful
effects with humans, it
is highly toxic to some
domestic animals,
including dogs and
horses.
With the animals,
theobromine can lead to
cardiac arrhythmias and
seizures.
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Caffeine