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Medicines and drugs. Depressants. depressants. What are depressants? Examples? Any use for them? Social and physiological effects of use/abuse?. depressants.
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Medicines and drugs Depressants
depressants • What are depressants? Examples? • Any use for them? • Social and physiological effects of use/abuse?
depressants • depress the central nervous system; they calm and relax the nervous system as they slow down the action of the brain, heart and other organs.
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 • lower economical production
Short term physiological effects • reduces tension, anxiety and inhibitions • impairs function of central nervous system
Long term physiological effects • liver damage/cancer • cirrhosis • increased blood pressure • heart disease or stroke • miscarriage and fetal abnormalities • tolerance and physical dependence
Synergetic effect of ethanol with other drugs Ethanol produces a synergic effect with other drugs i.e. their effect is enhanced in the presence of alcohol which can be dangerous e.g. with aspirin it can increase damage to stomach and cause bleeding. In the case of sleeping tablets and other sedatives it can cause coma or death.
Using potassium dichromate • Only used for detection in breath - breathalyzer. • 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. • Equations • oxidation: C2H5OH + H2O → CH3COOH + 4H+ + 4e− • reduction: Cr2O72− + 14H+ +6e− → 2Cr3+ + 7H2O 3C2H5OH + 16H+ + 2Cr2O72− → 3CH3COOH + 11H2O + 4Cr3+
intoximeter • 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 wavenumber 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 area under the peak is compared against a standard (e.g. allowed amount).
gas-liquid chromatography • Used for blood and urine samples. • Ethanol is separated from the urine or blood using gas-liquid chromatography as ethanol moves at a different rate through the stationary phase • Accurate as area underneath ‘ethanol’ peak in chromatogram indicates amount of ethanol in blood or urine.
