D4 Depressants • The effectsofdepressants • Use and abuse of ethanol • Techniquesused for detectionofethanol in urine and blood • Synergistic effectsofethanol and otherdrugs • Prozac, valium, mogadon • Described as antidepressantssincetheyrelieve depression
The effectsofdepressants • The central nervous system is depressed by interferingof the nerveimpulses in the neurons (nerve cells) • Slows down the functionsof the body, including mental activity • Calm, relative anxiety, mayinducesleep • Largedoses cause loss ofconsciousness, coma and death
Ethanol (alcohol) • Impairsjudgement and slows down reflexes • Most countrieshave legal limits for the amountofalcohol in the blood for motorists, airline pilots and peoplewhooperatesmachinery • Can be determined by breathalysers, gas liquidchromatography (GLC), intoximeters
Abuse ofalcohol; short term effects • Relaxing and anti depressing • Difficulties to speak, walk, violent behaviour, etc… • Social effects? Cost to society?
Use and abuse ofalcohol; long term effects • cardiovascular benefits from drinking 1 - 2 drinks per day • an increased risk of developing alcoholism, cardiovascular disease, malabsorption, chronic pancreatitis, alcoholic liver disease, and cancer • Social effects? Cost to society?
Ethanolanalysiswithbreathalysers Oxidation ofethanoltoethanalby dichromateions: Cr2O72- + 3C2H5OH + 8H+ → 2Cr3+ + 3CH3CHO + 7H2O Orange Green Oxidation ofethanoltoethanoicacid: 2Cr2O72- + 3C2H5OH + 16H+ → 4Cr3+ + 3CH3COOH + 11H2O Orange Green
Ethanolanalysiswith gas liquidchromatography (GLC) Separation accordingtoboilingpoint and polarity
Ethanolanalysis with infrared intoximeters Part A The Infrared Radiation is generated, usually from a quartz lamp.Part B The person breathes into this partPart C Where the breath comes outPart D The sample chamber, where the breath is stored.Parts E The lenses that focus the IR beam from the lamp.Part F The filter wheel, it filters out everything but specific wavelengths of the bonds in ethanol.Part G A photocell, which converts those wavelengths into an electric pulse.Part H The microprocessor, which interprets the electric pulse and calculates the Blood Alcohol Concentration based on the change in bond lengths in the ethanol. http://optiond.wikispaces.com/D.4.3
Infrared spectroscopy of ethanol Certain infrared wavelengths can be absorbed by ethanol:
Ethanolanalysis with fuel cell intoximeters By oxidizing ethanol, you get acetic acid, and two hydrogen atoms (two protons, and two electrons)The devices using the fuel cell technology to detect alcohol have two platinum electrodes, and a electrolyte material in between.The protons then move across the electrolyte, while the electrons move through wires connected to the platinum plates. On the other side, the protons and electrons bond with oxygen to form water. The current across the wire is measured, and sent to a microprocessor, which calculates the alcohol content. http://static.howstuffworks.com/flash/breathalyzer-fuel-cell.swf
Synergisticeffects of ethanol and otherdrugs • Sinceethanolsurpresses the central nervous system it has synergies with benzodiazepines, narcotics, barbiturates (sedatives) and solvents • With aspirin ethanolincreases the risk of stomach bleeding • Increases the risk of heavy sedation with anydrugaffectingthe central nervous system
Other Depressants • Certain medicines known as antidepressants are used to treat anxiety, stress, clinical depression and insomnia • Benzodiazepine: diazepam(Valium) • Nitrazepam(Mogadon) • Fluoxetine hydrochloride (Prozac)
Diazepam (Valium) – supresses the central nervous system • Fluoxetine (Prozac)- makes the mood-affecting serotonine more available • Nitrazepam(Mogadon)- treatment of moderate to severe insomnia, sedative and motor impairing properties
