medicines and drugs depressants. depressants depress the central nervous system (brain and spinal...
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depressants
depress the central nervous system (brain and spinal chord); change communication between brain cells by altering the activity of neurotransmitters. This causes a decrease in brain activity.
Terminology
Depression – clinical condition characterized by mood changes and loss of interest in normal activities.
The drugs used to treat depression are called antidepressants.
Effects of depressantsdose effect
low may exert little or no effect.
moderate may induce sedation, soothing, reduction of anxiety, impaired judgment
high may induce sleep, unconsciousness, slurred speech, altered perception
extremely high may cause organ failure or death
Short term physiological effects of ethanol abuse
reduces tension, anxiety and inhibitions
May become happy and outgoing
Flushed face due to dilated blood vessels
May become distracted or angry
impairs function of central nervous system
Slurred speech
Memory loss
Loss of balance/judgment
Vomit – can lead to aspiration
Dehydration due to increased urination
High doses - Loss of consciousness, coma, death
Long term physiological effects of ethanol abuse
liver damage/cancer
Cirrhosis (normal liver tissue is replaced by scar tissue and liver stops working properly)
increased blood pressure
heart disease or stroke
dementia
miscarriage and fetal abnormalities
Brain damage
tolerance and physical dependence
Social effect of ethanol use/abuse
increased risk when driving or operating machinery
involvement in violence or crime
relationship problems
taking time off work as a result of sickness or death associated with alcohol abuse
loss of income
hospital costs
Synergetic effect of ethanol with other drugs
Ethanol produces a synergic effect with other drugs (their effect is enhanced in the presence of alcohol) which can be dangerous
Ex. With aspirin it can increase damage to stomach and cause increased bleeding.
In the case of sleeping tablets and other sedatives it can increase sedation, or cause coma or death.
How to detect ethanol1. Potassium dichromate (VI) – The breathalyzer
Only used for detection in breath
In a positive result (i.e. presence of alcohol) the potassium dichromate changes form orange to green when ethanol is present as the potassium dichromate is reduced and the ethanol oxidized to ethanoic acid.
Equationsoxidation: C2H5OH + H2O → CH3CHO + CH3COOH
(ethanal + carbox acid)reduction: Cr2O7 2− + 14H+ +6e− → 2Cr3+ + 7H2O
How to detect ethanol
2/3. GLC – Gas-Liquid Chromatography
Used for blood and urine samples
Ethanol is separated from the urine or blood using gas-liquid chromatography
Produces a chromatograph which shows how much ethanol is in your system
Most accurate of the 5
How to detect ethanol
4. Intoximeter – IR Spectroscopy
Used for breath, blood and urine.
Infrared radiation is passed through breath, blood or urine. The C–H bond in ethanol causes radiation to be absorbed at a specific wavelength which is 2950 cm -1.
The intoximeter measures the amount of absorption which depends upon the amount of ethanol in the breath i.e. the more ethanol there is present the more IR is absorbed. The amount or peak is compared against a standard (e.g. allowed amount).
How to detect ethanol
5. Intoximeter – Fuel Cell
Used for breath
Ethanol is oxidized in the air to ethanoic acid and then to CO2 and H2O
The energy released in this reaction is converted into a detectable electrical voltage to measure ethanol concentration.
Other commonly used depressants
depressant structure: functional groups
Fluoxetine hydrochloride (Prozac®)
• aromatic benzene, ether, secondary amine, fluorine, chloride ion
diazepam/Valium®; amide/ketone/carbonyl; (tertiary) amine;
nitrazepam/Mogadon®;
amide/ketone/carbonyl; (tertiary) amine;
Anti-depressant
Sleeping pillsAnd muscle relaxants