OPTION D: MEDICINE AND DRUGS
D.4 Depressants
D.4.1
Describe the effects of depressants.
Depressants
 drugs that calm and relax the central nervous system
 slow normal brain function, slow breathing and lower blood pressure
 interfere with nerve impulse transmissions
 often described as anti-depressants because they relieve the symptoms of mentaldepression
ANY DEPRESSANT CAN ACT AS A TRANQUILIZER, SEDATIVE OR HYPNOTIC  DEPENDS ON DOSAGE
Tranquilizers
alcohol, valium (diazepam), librium
Sedatives
barbituates
mild reduction in nervous tension
and anxiety
does NOT produce sleep
more aggressive reduction in nervous
tension and anxiety
does NOT produce sleep
Hypnotics
higher doses of phenobarbital
chloral hydrate
√ produce sleep, coma, or death
D.4.2
Discuss the social and psychological effects of the use and abuse of ethanol.
Ethanol is both water and fat soluble and it can quickly crosses cell and tissue membranes
 Water soluble because both are polar molecules that can hydrogen bond to each other.
 Fat soluble because ethanol has some non-polar character and it is small.
Like other depressants, ETHANOL:
 interferes with neurons and slows down normal brain function.
 lower blood pressure, blood vessels dilate
Brain Area
Controls / Affects
Cerebral cortex
(Frontal Lobe)
Cerebellum
Parietal Lobe
Motor cortex
decision-making (moral, ethical & value judgments);
personality; self-control; language
coordination and balance
depth perception, other sensory perception (pain)
voluntary muscle control, reaction time
Hippocampus
Hypothalamus
Medulla
(brain stem)
memory and emotions
sexual arousal and performance
automatic body functions: heart rate, breathing
Common Short Term Effects of Ethanol
poor judgment; personality change  relaxed, confident
depresses inhibition  inappropriate behaviour, talkative
staggering
do not drink and drive
only ride with a sober driver
sleepy  sleep  coma  death
Physiological Effects
Vasodilation
smooth muscles of blood vessels relax
 capillaries near skin dilate  flushing, warmth
 veins and arteries dilate  reduced blood pressure
o Heart pumps harder to maintain blood pressure  coronary heart disease
o Rebound high blood pressure  hypertension, strokes, coronary heart disease
Liver
 detoxifies harmful chemicals in the blood, especially those that entered the body from the digestive tract
by converting them to less harmful forms
Over-taxing liver cells causes liver cells to die.
Cirrhosis – fibrosis (scar tissue) on the liver
Nerves
Ethanol does not kill brain cells,
it merely damages the ends of the neurons (dendrites) so the way the neuron communicates is altered.
Long term effect: memory problems, confusion, lack of muscle coordination
Pregnancy
increased risk of miscarriage, low birth mass, developmental problems,
FAS (fetal alcohol syndrome) – physical and mental birth defects from shared blood containing high alcohol levels
Other Long Term
Synegistic effects
gastritis, peptic ulcers, tolerance, dependence, anxiety, depression, malnutrition
the effect of the combination of two drugs is greater either drug taken alone
Alcohol + other depressants  risk of heavy sedation, coma, death
Alcohol + Aspirin  increased risk of stomach bleeding
Alcohol + cocaine  vasoconstriction, high blood pressure, irregular heart rate