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 (D.4) Ali Q, Sohrab R.
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.