Presentation on theme: "Depressants (D.4) Ali Q, Sohrab R.. Depressants? Drugs which depress the CNS. Interfere with transmission of nerve impulses in the neurones. Slow down."— Presentation transcript:
Depressants? Drugs which depress the CNS. Interfere with transmission of nerve impulses in the neurones. Slow down bodily functions including mental activity. Most commonly taken depressant is alcohol (H 3 C-CH 2 -OH) Sometimes called anti-depressants. Relieve symptoms of mental depression.
Effects? 0 Low Doses: 0 Little, or no effect. 0 Moderate Doses: 0 Feeling of calm, relieve anxiety. 0 Large Doses: 0 Induce sleep. 0 Extremely high Doses: 0 Death.
Alcohol? 0 In Medicine: 0 Alcohol used as antiseptic before injections and to harden skin. 0 Drinking: 0 Psychological and physical dependence; alcoholism. 0 Huge social costs due to: 0 Road accidents, violent behaviour, family breakdowns.
Short Term Effects. 0 Moderate quantities: 0 Feeling of relaxation, confidence, increased sociability. 0 Dilates small blood vessels. 0 Flushing and feeling of warmth. 0 Judgement, concentration, progressively impaired. 0 Violent behaviour. 0 Slurred speech, loss of balance. 0 High quantities: 0 Loss of consciousness. 0 Risk of death from inhalation of vomit or stoppage of breathing.
Long Term Effects. 0 Heavy Drinking: 0 Severe liver disease. 0 Cirrhosis, liver cancer. 0 Linked with coronary heart disease, high blood pressure, strokes, increasing risk of dementia. 0 Can cause miscarriage and foetal abnormalities during pregnancy. 0 Sudden discontinuation by heavy users can cause delirium tremens (the ‘DTs’). 0 Severe shaking, can last up to four days.
Breathalyzer & Chromatography 0 Breathalyzer: 0 Acidified potassium or sodium dichromate(VI) crystals turn green as they are reduced by alcohol to Cr3+. 0 Chromatography: 0 Blood or urine sample using gas liquid chromatography
0 Absorption of infrared radiation: 0 C-H bonds in ethanol absorbs infrared radiation of a particular wavelength
0 Alcohol enhances the effect of other drugs because it depresses the CNS (Synergistic effect) 0 Fatal. 0 Alcohol taken with Aspirin increases the risk of stomach bleeding
Other Depressants 0 Commonly prescribed to: 0 Reduce anxiety, relieve stress, help insomnia. 0 These include the benzodiazepines and Prozac. 0 Usually only prescribed for limited period while counselling or psychotherapy are used, as these an induce dependence. 0 Also used as a premedication in hospitals before general surgery.