Option D: Medicines and Drugs

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Lines of defence of the body

1st L.oD.  (barriers to prevent entry)

- skin

- mucus membranes

- closures + scretions of natural openings 

2nd L.oD. (attack invaders)

- white blood cells (engulf invaders)

- blood clotting (prevent loss of blood + further invasions)

- inflammatory response

3rd L.oD. (immune system)

- white blood cells (produce specific proteins, antibodies, to recognize + destroy invaders)

- memory cells (enable body to fight repeat invasion of same organism more effectively)

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Reduces ability of blood to clot

Negative side effects:

- irritation

- ulceration of sotmach

- people can be allergic

- Reye's syndrome - potentially fatal liver + brain disorder

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Reduces production of prostaglandins in brain, not rest of body

Safe in correct dose

Safe for children

Negative side-effects:

- blood disorders

- overdose = liver, kidney + brain damage

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- second stage treatment w/ paracetamol + aspirin

- cough treatment


- may not completely relieve pain

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- management of severe pain (eg. advanced cancer)

- treatment of diarrhoea


- constipation

- dependence

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Diamorphine / heroin


- relief of severe pain

- feeling of well-being + contentment

- dulling of pain, lessening of fear + tension

- euphoric effects

- most rapidly acting 


- Constipation, loss of apetitie, poor nutrition

- Strong addiction

- Rapidly increasing dependence

- Death

- Cost of drugs

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Dosage Effects of Depressants

Low: calmness, drowsiness, increaaed spoantaneity, slower mental activity

Moderate: soothing, reduction of anxiety, altered perception, very relaxed muscles

High: slurred speech, faltering movement, altered perception, sleep induced

Extremely high: low breathing + heart rates, sleep, coma, death

Low / Moderate = tranquilizers = alcohol, valium

Moderate / High = sedatives = barbiturates

High / extremely high = hypnotics = chloral hydrate

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Abuses of ethanol

Short term: - loss of self restraint

- memory, concentration + insight impaired

- loss of balance + judgement

- violent behaviour

- 'hangover' - dehydration + headache due to increased urine output

- high doses = vomiting, loss of conciousness, death

Long term: - Dependence / alcoholism

- Liver disease (cirrhosis, cancer)

- coronar heart disease

- high blood pressure

- premanent brain damage

- deterioration of social aspects of life + productivity    - fetal alcohol syndrome

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Synergistic effects of ethanol

Ethanol has potential to increase activity of other drugs = synergy

Aspirin - increased bleeding of stomach lining + ulcers

Barbiturates - heavy sedation, possibly coma

Tobacco - increase incidence of cancers (intestines, liver)

Other drugs - interfere w/ metabolism - liver

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Analysis of breath for detecting alcohol

Test = breath analyser / bearthalyser

Contains acidified potassium dichromate (VI) crystals

Turn from orange to green when reduced by ethanol

Extent of colour change measured by photocell - determines ethanol concentration

More accurate = infrared spectroscopy

Different molecules cause different absorption bonds in infrared spectrum

Results of particular bonds + functional groups

Ethanol absroption band = 2950 cm-1

Size of peak determines concentraiton

Doesn't always work on diabetes who breathe out ketone which shows false positive

Intoximeter - fuel cell - ethanol oxidized in presence of catalyst to ethanoic acid, then water + CO2 - converts energy released into detectable electrical voltage - concentration determined

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Ethanol analysis in blood and urine

Gas-liquid chromatography - only done in laboratory - very accurate

Blood / urine vaporized + injected into stream of inert gas (mobile phase) over surface of non-volatile liquid (stationary phase)

Components of vapour move at different rates depending on boiling points + relative solubility

Leave column holding liquid phase after specific interval of time = retention time

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Small doses: - increase mental alertness + physical energy

- side effects: dilation of pupils, decreased apetite, blurred vision + dizziness

Regular use: - dependence + teloerance

- severe depression

- reduced resistance to infection

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Short term effects: - increases concentration

- relieves tension + boredom

- helps counter fatigue

- increases heart rate + blood pressure

- decreases urine output

Long-term effects: - high blood pressure

- increases risk of heart disease

- coronary thrombosis

- increases fatty acids in blood - stroke

- over-stimulation of stomach acids - peptic ulcers

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Consumption in small amounts:

- enhancement of mental energy, alertness + ability to concentrate

- acts as diuretic - increases volume of urine - can cause dehydration

Consumption in large amounts:

- can cause anxiety, irritability, insomnia

- dependence - withdrawal symptoms of headaches + nausea

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LSD / lysergic acid diethyl amide

Relatively large , non-polar, soluble in membranes so able to enter brain easily

Synthesized form ergot - grain fungus in rye

Takes effect within 20 mins + lasts up to 12 hours

Effects: - potent hallucinations

- distortion of body + crawling geometric patterns

- impaired judgement

- hypertenison

- dilated pupils

- changes to body tempetature + heart rate

- unpredictable mood swings from euphoria ('good trip') to depression + panic ('bad trip')

- can lead to trigger flashbacks, 'latent psychosis'

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Smaller molecule, not so soluble in membranes so less able to enter brain

Extracted from flowering heads of peyote cactus

Takes effect almost immediately + last 6 hours

Effects: - 1000-3000 times less potent than LSD

- subjective hallucinations, depending on individual

- anxiety

- static tremors

- psychic disturbances w/ vivid visual halluctinations

- abdominal pain

- nausea

- diarrhoea

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Contains ionic groups, least soluble in membranes

Extracted from 'magic mushrooms'

Takes effect rapidly + shorter lasting than mescaline

Effects: - Subjective hallucinations similar to, but milder than mescaline

- Pleasant mood, some apprehensive

- compulsive movement + inappropriate laughter

- vertigo + dizziness

- numbness

- muscle weakness

- drowsiness

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Takes effectc within 15 mins + lasts up to 4 hours

Effects: - depresses central nervous system + causes mental relaxation + euphoria

- loss of inhibitions

- alteration of perception of time + space

- palpitations

- loss of concentration

- light-headedness

- weakness

- sense of floating

- at high doses = depression of respiration + collapse

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Legal status of Cannabis

Arguments for illegal status: - effects on body

- dependence

- cost of medical care for those suffering long-term effects

- people being encouraged to take 'hard' drugs

Counter arguments: - no proven link between it and intake of more addictive drugs

- no more damaging than tobacco + alcohol

- on open market, would protect users from dealing w/ gangs

Medical aspects: - in treatment of advanced cancers + AIDS - offers relief form nausea + vomiting

- can have positive effects in treatment of glaucoma, asthma, convulsive disorders

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