IB chemistry SL revision Option D

1. Pharmaceutical productsWhat are the effects of medicines and drugs on the functioning of the body?

alter the physiological state, including consciousness, activity level or coordination

alters incoming sensory sensations

alter mood or emotions

What are the stages involved in the research, development and testing of new pharmaceutical products?1. Identify disease, a target molecule2. Identify target e.g. gene or enzyme which is necessary for disease to progress.

3. Identify lead molecule that can act on gene/enzyme in the disease organism or host and isolate or manufacture it.

4. Preclinical trials: in vitro and in vivo:5. Clinical trials : on people/placebo effect6. Submission of reports on the drug and its trials to international or national regulatory bodies.

7. Monitoring of the drug after it has been launched; molecule might need further structural changes.

What are the different methods of administering drugs? Oral: taken in by the mouth e.g. tablets, syrups, capsules. Parenteral - by injection: intravenous: into a vein of the blood stream used for immediate impacts as its fastest method; drug is immediately pumped around the body by the blood. intramuscular i.e. into the muscles, e.g. many vaccines, local anaesthetics, usually used when a large dose needs to be administered. subcutaneous: in the layer of the skin directly below the cutis (dermis and epidermis) e.g. dental injections, morphine, insulin. Slow. Inhalation: e.g. medication for respiratory conditions such as asthma. Rectal: inserted into the rectum e.g. treatment for digestive illnesses, drug absorbed into the blood stream. Skin patches: e.g. hormone treatments.

What is the therapeutic window of a drug?The therapeutic window is the range in concentration over which a drug can be safely administered to a typical population.

The lowest level of concentration is the called the effective level (therapeutic level) or ED50; below this level the drug loses its therapeutic effect

The highest level is the toxic or LD50 level (= the dose needed to kill 50 % of (animal) population) above which adverse side-effects can occur

What does tolerance mean?Tolerance refers to the bodys reduced response to a drug i.e. its therapeutic effect is less than what it is intended, usually as a result of taking the drug over a long period of time. As a result more of the drug needs to be taken to achieve the same initial physiological effect

What are side-effects of a drug?Side-effects are physiological effects which are not intended and therefore undesired (intended = therapeutic effects). Some side effects can be beneficial e.g. aspirin also protects against heart disease.

Can be benign e.g. cause drowsiness or adverse, e.g. cause damage to organs.

What is the placebo effect?The placebo effect occurs when a person experiences a positive therapeutic (in particular with pain killers) effect because they believe they have been given a medicine although the substance given is not a medicine, instead a placebo has been administered; the human body is fooled into healing itself naturally. Placebo is used as a control to measure the real effectiveness of the drug which is the difference between the effects experienced by the patients who took the drug and those patients who did not.

Patients and administrators do not know which patients have taken the placebo.

What are advantage and disadvantages of oral administration? Easy to take, no special equipment needed.

Slow to have effect, stomach can decompose/change medicines, can cause stomach bleeding.

When are injections the best method of administration? When an immediate effect is needed

Effect might be needed for the whole body

Direct delivery to the area the medicine is needed

Medicine will be broken down by stomach

2. AntacidsHow can excess acidity in the stomach be reduced by the use of different bases?By adding antacids such as aluminium hydroxide, magnesium hydroxide and sodium hydrogencarbonate. These chemicals can neutralize the acid as they have OH- or HCO3- ions which can react with H+ from acid to form water and salt.

Why are alginates added to antacids?Alginates produce a neutralizing layer on top of stomach contents and this prevents acid in the stomach from rising into the oesophagus and causing heartburn.

Why is an anti-foaming agent added to antacids that have carbonate in them?Anti- foaming agents such as dimethicone reduce the bloating of the stomach as a result of the carbon dioxide production.

3. Analgesics

How do mild analgesics prevent pain?by interfering with the production of substances, such as prostaglandins, that are produced by injured tissues and that cause pain, swelling or fever.

How do strong analgesics prevent pain?by temporarily bonding to receptor sites to pain impulses in the brain or other parts of the central nervous system such as the spinal cord. This prevents the transmission of pain impulses i.e. blocking the signal without depressing the central nervous system.

Name examples of mild analgesics.aspirin, paracetamol

Name sxamples of strong analgesics.codeine, morphine, heroine

What are the advantages of using aspirin? reduces fever more effectively antipyretic (=drug which reduces fever)

also useful in preventing the recurrence of heart attacks and strokes and also thins the blood (beneficial side-effects) and reduces blood clotting

also anti-inflammatory reduces inflammation or swelling

What are disadvantages of using aspirin? ulceration

stomach bleeding due to its acidic properties

allergic reactions

Reyes syndrome in children (a potentially fatal liver and brain disorder) so not suitable for children

What are the advantages of using paracetamol? reduces fever - antipyretic

very safe in the correct dose as it does not upset the stomach or cause bleeding

suitable for children

What are disadvantages of using paracetamol? can, in rare cases, cause blood disorders and kidney damage.

easier to overdose and overdosage can lead to serious liver damage, brain damage and even death.

not a good anti-inflammatory

What do the structures of morphine, codeine and heroine have in common? All three have the aromatic benzene ring, a tertiary amine, a double bond and an ether group.

How are the structures of morphine, codeine and heroine different?Both morphine and codeine also have a hydroxyl group. Heroine has 2 ester groups.

What are the advantages of using morphine and its derivatives? strong analgesics and therefore can relieve extreme pain wide therapeutic window relieves anxiety induces relaxation can be administered intravenously which results in faster distribution of drug

What are the disadvantages of using morphine and its derivatives? euphoria, lack of self-control even dangerous behaviour kidney failure. addiction or physical dependence which leads to withdrawal symptoms when drug is not taken e.g. restlessness, sweating, fever, cramping, tolerance can become an issue with this type of drug as more of the drug needs to be taken to achieve the same effect; in order to achieve the desired effect heroin users may take doses which exceed the lethal dose Social: heroin users are more likely to commit crimes to pay for gradually increasing doses of the drug diversion of energy and money; loss of job when administered intravenously can lead to transmission of dangerous infections e.g. AIDS.

4. Depressants

What are effects of a low dose of depressant?may have little or no effect.

What are effects of a moderate dose of depressant?may induce sedation, soothing, reduction of anxiety, impaired judgement

What are effects of a high dose of depressant?may induce sleep, unconsciousness, slurred speech, altered perception

What are effects of a very high of depressant?may cause organ failure, coma or death

What are the social effects of alcohol use and 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

What are the short term physiological effects of alcohol use/abuse? reduces tension, anxiety and inhibitions

impairs function of central nervous system

dehydration

high dose can cause vomiting, unconsciousness

What are the long term physiological effects of alcohol use/abuse? liver damage/cancer cirrhosis liver disease increased blood pressure heart disease or stroke miscarriage and fetal abnormalities tolerance and physical dependence

What is the synergetic effect of using alcohol with other drugs?the effect of the other drugs is often 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.

How is potassium dichromate used to detect alcohol? Used in a breathalyzer; in a positive result (i.e. presence of alcohol in the breath) 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.

How does an intoximeter detect alcohol?Infrared radiation is passed through breath, blood or urine sample. The CH 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 amount or peak is compared against a standard (e.g. allowed amount)

How does chromatography help to detect alcohol?Ethanol is separated from the blood or urine using gas-liquid chromatography; area under ethanol peak on chromatogram indicated amount of ethanol in blood or urine

What are other common depressants?prozac, valium, mogadon

Describe the structure of Prozac.aromatic benzene, ether, fluorine, amine, chloride ion

Describe the structure of Valium.amide, aromatic benzene secondary amine, chlorine,

Describe the structure of Mogadonamide,aromatic benzene, secondary amine, NO2

5. Stimulants

What are the short term physiological effects of stimulants? increased heart rate, blood pressure, breathing rate dilation of pupils constriction of arteries sweating increased alertness and concentration decreased appetite stimulating effects.

What are the long term physiological effects of stimulants? increased risk of heart disease

increased blood pressure

coronary thrombosis

stomach ulcers.

tolerance: which leads to increased use as increased amounts needed to produce same effect; increasing amounts cause damage/death/overdose/lethal dose

What are amphetamines?amphetamines mimic the effects of epinephrine or adrenaline which stimulates the sympathetic nervous system and they are therefore known as sympathomimetic drugs.

What do amphetamines and epinephrine have in common?an aromatic benzene ring and an alkyl chain

What are amphetamines and epinephrine different?amphetamines have a primary amine whilst epinephrine has 3 hydroxyl groups and a secondary amine

What are the short term effects of nicotine? increased heart rate increased blood pressure reduced urine output increased concentration

What are the long term effects of nicotine? increased risk of cancer or stroke heart disease / thrombosis stomach ulcers emphysema bronchitis shortage of breath coughing bad breath yellowing of teeth or fingers adverse effect on pregnancy addiction to tobacco

reduction in capacity of blood to carry oxygen; withdrawal symptoms / weight gain (on quitting);

What are the effects of caffeine?caffeine is a stimulant. When consumed in large amounts it can cause anxiety, irritability and sleeplessness. It is a weak diuretic

Compare the structure of caffeine and nicotine.both have aromatic benzene and tertiary amine group; in fact caffeine has three tertiary amine groups.

Caffeine also has two carbonyl groups.

6. Antibacterials

What contribution did Alexander Fleming make to the development of penicillin?discovered that penicillin inhibited growth or killed bacteria

What contribution did Florey and Chain make to the development of penicillin? overcame the problems associated with isolating and concentrating penicillin as Penicillin G showed that penicillin is harmless and effective on mice; first to use penicillin on a human; grew penicillin in large amounts;

How does penicillin work?Penicillins work by interfering with the chemicals that a bacteria needs to form a cell wall. This prevents the formation of cross-links within the cell wall. As a result the bacterial cell absorbs too much water and bursts as the result of increased osmotic pressure.

What are the advantages of modifying the side-chain of penicilins? resistant to penicillinase enzyme which is an enzyme which can break down penicillin G and which is found in some bacteria; stops bacteria from destroying penicillin and becoming resistant to them resistance to breakdown by stomach acid (so can be taken orally).

What is patient compliance?Patients taking antibacterials as prescribed i.e. take all tablets and in the correct dose.

Why is important patient compliance important?If patients not being compliant allows bacteria to become resistant.

What are the effects of overprescription of penicillins or antibacterials? leads to resistance by the bacteria to penicillin which makes penicillin less effective; bacteria produced penicillinase, an enzyme which destroys penicillin resistant bacteria reproduce and pass on their resistance to succeeding generations useful bacteria may be killed

7. Antivirals

How are viruses different from bacteria? viruses are not self-reproducing as they need a host cell to multiply; viruses insert DNA into host cells viruses lack any metabolic functions so they do not grow, feed or excrete

viruses consist only of genetic material and protective coating viruses are smaller than bacteria viruses mutate/multiply (much) faster than bacteria

What are the different ways in which antivirals work? altering the host cells genetic material so that the virus cannot use it to multiply preventing the viruses from multiplying by blocking enzyme activity within the host cell. preventing viruses from entering host cell and binding to cellular receptors targeted by the viruses preventing the release of viruses from the cell

What difficulties are associated with solving the AIDS problem? HIV viruses can mutate rapidly HIV viruses have similar metabolism to the metabolism of the host cell so any drug could also damage host cell high price of antiretroviral drugs socioeconomic cultural issues;

PAGE 1IB revision Option D