Option D: Medicines and Drugs
- Created by: Théa
- Created on: 10-05-15 19:10
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)
Aspirin
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
Paracetamol
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
Codeine
Advantages:
- second stage treatment w/ paracetamol + aspirin
- cough treatment
Disadvatages:
- may not completely relieve pain
Morphine
Advantages:
- management of severe pain (eg. advanced cancer)
- treatment of diarrhoea
Disadvantages:
- constipation
- dependence
Diamorphine / heroin
Advantages:
- relief of severe pain
- feeling of well-being + contentment
- dulling of pain, lessening of fear + tension
- euphoric effects
- most rapidly acting
Disadvantages:
- Constipation, loss of apetitie, poor nutrition
- Strong addiction
- Rapidly increasing dependence
- Death
- Cost of drugs
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
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
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
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
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
Amphetamines
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
Nicotine
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
Caffeine
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
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'
Mescaline
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
Psilocybin
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
Cannabis
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
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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