Medicines and
drugs
Stimulants
stimulants
•nicotine, caffeine, amphetamines
•the intention of these drugs is to have
similar effects to adrenaline which is a
natural stimulant.
•amphetamines have similar structures
to adrenaline.
stimulants
• affect central nervous system; act on
neurotransmitters which are chemicals
that acts as messengers and stimulate
pathways
• increase activity of the brain
• largely opposite to depressants
physiological effects
short term
 increased heart rate, blood
pressure, breathing rate
 dilation of pupils
 constriction of arteries
 sweating
 increased alertness and
concentration
 decreased appetite
 stimulating effects.
long term
 increased risk of heart
disease
 increased blood pressure
 coronary thrombosis
 stomach ulcers.
 tolerance:
 increasing amounts cause
damage/death/overdose/letha
l dose
amphetamines
• group of drugs which mimic the effect of adrenaline
• classified as symphatomimetic drug as it stimulates the
symphatetic nervous system
• adrenaline or epinephrine = hormone released in times of
stress e.g. pain, cold, fear, …
• response to increased adrenaline:
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increased heart beat/blood pressure
Increased blood flow to brain and muscles
Increased air flow to lungs
Increased mental alertness
compare
• Common: both amphetamines and epinephrine
have a phenyl-ethyl-amine chain which is benzene
ring linked to an amine group by a carbon chain
• Different: functional groups
• amphetamines:
• primary amine
• epinephrine:
• 3 hydroxyl groups
• secondary amine
nicotine
• A nicotine molecule contains the following
functional groups: a tertiary amine, aromatic
benzene ring structures with nitrogen atoms in
them, and double bonds (alkene functional group).
physiological effects nicotine
short term effects
 increased heart
rate
 increased blood
pressure
 reduced urine
output
 increased
concentration
long term effects
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increased risk of cancer or stroke
heart disease / thrombosis
stomach ulcers
emphysema
bronchitis
shortage of breath
coughing
bad breath
yellowing of teeth or fingers
adverse effect on pregnancy
addiction to tobacco
reduction in capacity of blood to carry
oxygen;
withdrawal symptoms / weight gain (on
quitting);
caffeine
• Caffeine is a psychoactive
stimulant. When
consumed in large
amounts it can cause
anxiety, irritability and
sleeplessness. It is a weak
diuretic i.e. causes the
body to lose more water
than it takes in
• Its structure is similar to
nicotine.
structure of caffeine
• aromatic rings containing both carbon
and nitrogen – like nicotine
• tertiary amine group
• two amide groups (- N – C = O)
caffeine
consumption in
small amounts
• increased mental
alertness
• greater ability to
concentrate
•diuretic;
dehydration
large amounts
•can cause anxiety,
irritability, nausea
•dependence