Transcript stimulants

CHEMISTRY MEDICINES
AND DRUGS
STIMULANTS
Stimulants are drugs that
> stimulate the brain and the central
nervous system
> increase the state of mental
alertness
> decrease appetite
A) Amphetamines
B) Caffeine
C) Nicotine
Adrenaline (epinephrine)
is a natural stimulant produced in the
adrenal gland.
> it is released when in stress or fear
> it controls
- heart/breathing rate
- pupil dilation
- sweating
AMPHETAMINES
Amphetamines are chemically related to adrenaline.
•
They both derive from phenylethylamine.
•
They are sympathomimetic drugs which mimic the
effect of stimulation on the nervous system by increasing
the levels of dopamine.
•
Amphetamines were initially used to treat narcolepsy and in
WW II were used by soldiers to combat fatigue.
• Later during the 50’s and 60’s they were used as slimming
pills.
• Regular use can lead to both tolerance & dependence.
•
Short-term effects:
- increase in heart rate and breathing
- insomnia
- dilation of the pupils
- decrease in appetite
- possible fatigue and depression
•
Long-term effects:
- weight loss
- constipation
- emotional instability
- dependence
•
Phenylethylamine
(love molecule)
- “high” feeling of lovers
- also found in chocolate
Dopamine
Transmits to neurons
signals of
- joy
- happiness
- excitement
Amphetamine
- stimulant
- suppresses appetite
- treats narcolepsy
Methamphetamine
(“speed”)
- potent stimulant
- very addictive
- severe withdrawal symptoms
- “meth mouth”
Ecstasy
- potent stimulant
- designer drug
- can be fatal
- neurotoxic
CAFFEINE
•
It is the most widely used stimulant in the world.
It is present in coffee, tea, chocolate and cola drinks
and is also found in some pain killers or other medicines.
•
People that consuming 400 mg of caffeine a day may
have dependence & physical side effects.
•
Like nicotine, morphine, codeine and cocaine, caffeine
is also an alkaloid.
•
Alkaloids are nitrogen-containing compounds of plant
origin containing heterocyclic rings and a tertiary amine
group.
•
Theobromine has a similar structure to caffeine, which
is also found in chocolate. (It does not contain bromine!)
•
caffeine
theobromine
Effects at low doses:
- respiratory stimulant
- weak diuretic
- enhances concentration and alertness
- reduces migraines (constriction of blood vessels)
•
Effects at high doses:
- anxiety
- irritability
- sleeplessness
•
NICOTINE
One third of the world’s population is addicted to
smoking because tobacco contains nicotine
•
Nicotine produces psychological and/or physical
dependence
•
Nicotine builds up tolerance
•
Stopping smoking can produce temporary symptoms
like a craving for tobacco, nausea, weight gain,
insomnia, irritability and depression
•
Short-term effects:
- stimulates nervous system
- increases heart rate and blood pressure
- increases concentration
- constricts blood vessels
- stresses heart
- reduces urine output
•
Long-term effects:
- increases risk of heart disease coronary thrombosis
- inhibits ability of blood to carry oxygen (CO)
- excess acidity > peptic ulcers
- mouth/lung cancer
- adverse effects on pregnancy
Both compounds are heterocyclic with one
or more carbon atoms in the ring replaced
by nitrogen atoms.
They both contain a tertiary amine group
caffeine
nicotine