Option D Flashcards
Define drug or medicine
A substance that alters physiological state, moods and emotions, levels of consciousness and incoming sensory information
What are the 5 ways to take drugs/medicines?
Oral
Inhale
Injection
Rectal
Topical
Define parentereal
Not involving the digestive system
Which methods of drug administration can be self-administered?
Oral
Topical
Usually:
Inhale
Rectal
Sometimes:
Injection
What is the advantage of oral administration of medication?
Easy and self administered
What is the disadvantage of oral administration of medication?
Can effect the stomach
What is the advantage of inhalation of medication?
Easy and fast delivery to the bloodstream
What is the advantage of injection?
Can be fast depending on method
What are the three types of injection?
Intravenous
Subcutaneous
Intramuscular
Describe intravenous injection
Direct to the vein - fast
Describe subcutaneous injection
Under the skin (into the fatty layer)
Describe intramuscular injection
Deep into the muscle
Should polar or non polar substances be injected intravenously?
Polar
Should polar or non polar substances be injected subcutaneously?
Non-polar
Should polar or non polar substances be injected intramuscularly?
Polar
What is the advantage of rectal administration of medication?
Avoids going through the stomach
Good absorption in the intestines (especially for digestive problems)
What is the advantage of topical administration of medication?
Easy, self administered and local
Define lethal dose
Dose required to kill 50% of the population
Define effective dose
Dose required to bring across a notable effect in 50% of the population
Define toxic dose
Dose required to bring about a toxic effect in 50% of the population
Define therapeutic index in animals
Lethal dose/ Effective dose (ideally high)
Define therapeutic index in humans
Toxic dose/ Effective dose (ideally high)
Define therapeutic window
The difference between lethal dose and effective dose
Define tolerance
Resistance of a body to the effects of a drug
What are the two types of tolerance?
Genetic - your natural resistance depending on your genetics
Acquired - from repeated exposure
Define placebo effect
The bodies ability to heal itself naturally without the need for drug. Effectivness of a drug
What can placebo groups be useful for?
To compare against to see if a drug is effective
Define side effects
Not the real effect for which a drug is taken but may occur additionally when taking it
Define risk to benefit ratio
A comparison between the bad things that the drug could do to you compared to the benefit that you will receive from taking the drug
Define OTC
Over the counter
Drugs available for you to buy in a supermarket/shop without regulation
Define on prescription
Drugs only issued by agreement of doctor
Define bioavailability
Amount of drug that reaches the target organ
What is the pH of stomach acid?
~2
[HCl] = 0.01M
What is an ulcer?
Where the stomach acid attacks the stomach where the lining is thin
How can ulcers be treated?
Increasing pH by adding a base
What are the suitable bases to treat ulcers?
Mg(OH)2, Al(OH)2 or NaHCO3
What are the side effects of Al(OH)2?
Alzheimer’s
What are the side effects of Mg(OH)2?
Diarrhoea
What does ranitidine (zantac) do?
Histamine inhibitor
How does histamine effect the stomach?
Histamine stimulates the acid making cells
What does omeprazole (nexium) do?
A proton pump inhibitor which prevents acid from being released in the stomach
What two things can omeprazole fight?
Heartburn
Stomach ulcers
How does heartburn work?
Acid in the stomach prays up in to the oesophagus and attacks the tissues
Define zwitterion
An ion with both negatively and positively charged groups
Give an example of a zwitterion
Ranitidine
What are the side effects of ranitidine and omeprazole?
Short term: Diarrhoea
Long term: Osteoporosis, food allergies and intolerance
Define analgesis
Pain relief
Define and name mild analgesics
Prevent the release of neurotransmitters from the injury site (aspirin, paracetamol and ibuprofen)
Define and name strong analgesics
Prevents neurotransmitters from reaching the brain by blocking the receptor sites (morphine, codeine and heroin)
Where is aspirin originally from?
Salicylic acid and ethanoic acid to reduce side effects of the salicylic acid
What potential side effect of aspirin makes it not prescribed to childern?
Reye’s disease (fatal)
Define antipyretic
Fever reducing
Which common drug is anticoagulalent?
Aspirin
Which common drug is antipyretic?
Paracetamol and ibuprofen
Which common drug is antiinflammatory?
Ibuprofen
Which common drug is a mild analgesic?
Aspirin
Paracetamol
Ibuprofen
What are the side effects of aspirin?
Stomach ulcers
What are the side effects of paracetamol?
Liver, brain, kidney damage
What are the side effects of ibuprofen?
Liver, kidney and stomach damage
Which mild analgesic should be taken after food?
ibuprofen
Which common mild analgesic may prevent cancer and Parkinsons?
Aspirin
Define retrosynthesis?
Working back from a target compound to make the desired compound out of a variety of sources
Define alkaloids
Drugs of plant origin containing a tertiary amine and heterocycle
Which strong analgesics are alkaloids?
Morphine
Codeine
(Diamorphine)
Which strong analgesic is a derivative of alkaloid?
Diamorphine (heroin)
What are the opiates?
Drugs from poppy seeds
Morphine and codeine (and diamorphine)
How is diamorphine produced?
Esterification of morphine with vinegar
Why is heroin more dangerous than morphine?
It is less polar and therefore dissolves well in fats and can more easily cross the blood brain barrier, making it more addictive
What are the short term effects of strong analgesics?
Euphoria
Depressed nervous system
Loss of cough reflex
Nausea
Coma
Death
What is defined as a short term effect?
Something that occurs within minutes or hours
What is defined as a long term effect?
Something that occurs over months or years (usually after repeated exposure)
What are the long term effects of strong analgesics?
Constipation (Direct)
Loss of libido (Direct)
Loss of period (Direct)
Poor nutrition
Risk of HIV (needles)
Social problems
Prostitution
Loss of job
(Direct) means directly due to drug use whilst the others are secondary
What are the sections of a bacteria?
Cell membrane
Ribosomes
DNA
Cytoplasm
Cell wall
How do bacteria replicate?
Binary fission
When is bacteria most vulnerable and why?
When they are replicating as the cell wall gets thinner
How does penicillin work?
It mimics the units needed for healthy cell wall construction
What is the first example of chemistry being used to treat bacterial infection?
Paul Ehrlich used salvarsan to treat syphilis
What led to the discovery of penecillin?
Alexandra Fleming noticed bacteria would not grow in mold
Who first used penecillin?
Florey and Chain
What occurred in the first ever treatment with penicillin?
Penicillin ran out halfway through and the policeman (patient) died despite having been dramatically better
When did penecillin use become widespread?
World War II
Which part of the penicillin ring mimics the amino acids needed for cell wall construction?
Square B lactam ring has strained angles which can be easily opened to mimic these amino acids
Define narrow spectrum antibiotics
Effective against a small number of species
Define broad spectrum antibiotics
Effective against a wide number of species
What does overuse of antibiotics lead to?
Bacterial resistance rendering them ineffective
What are the causes of overuse of antibiotics?
Prescription when not needed
Added to animal feed as a preventative (e.g.: chickens full of penicillin)
How can cancer be treated?
Radiotherapy with radio isotopes
What are the two categories of waste?
LLW (Low level waste)
HLW (High level waste)
What are the properties of low level waste?
Low activity, short half-life and decays quickly
How are protective clothing maintained sterile?
Treated with radiotherapy
(Iodine -131, Strontium-89 or Samarium-153)
Give examples of low level waste items?
Gloves, packaging, protective clothing
How is low level waste disposed of?
Landfill or the sea
What are the properties of high level waste?
High activity, long half-life and decays slowly
Define in vivo
In living
Define in vitro
In glass (Latin)
How is high level waste disposed of?
Vitrification and burying
Define vitrification
Turned into glass
How should antibiotic waste be correctly disposed of?
In pharmacy
Why must antibiotic waste not be sent to landfill?
Waste in the environment (soil and water) may also lead to resistance
What are the three types of solvent?
Chlorinated, non-chlorinated and aqueous
What constitutes as aqueous solvents?
Water, NaCl (aq) etc…
What constitutes as non-chlorinated solutions?
Methanol, ethanol, esters
What constitutes as chlorinated solutions?
CCl4, CHCl3 etc…
How are chlorinated solutions disposed of?
Burned at very high temperatures to prevent the formation of toxic dioxins
How are non-chlorinated solutions disposed of?
Recycled
Heavy metals are extracted and then both metals and solution are either recycled or burnt for energy
How are aqueous solutions disposed of?
In the sea
(almost infinite dilution)
What is the greatest disadvantage of non-chlorinated solution disposal?
Expensive
What is the greatest disadvantage of chlorinated solution disposal?
If incomplete combustion occurs, toxic dioxins may be produced
What are the aims of “Green Chemistry”?
Reduce pollution, consumption (of raw material and energy and high yield (low waste)
What 5 things must we look at in chemistry to be as “green” as possible?
High atom economy
Environmental factor
Carbon efficiency
Reduce steps in reaction (less waste)
Use greener and safer solvents
What is environmental factor?
Total waste (kg) / Mass of product
Total waste includes water used in washing, gloves, packaging etc…
What is carbon efficiency?
Amount of carbon in product/ total carbon in reactants
Describe the differences between bacteria and viruses
Viruses are smaller, not strictly alive and require a host to reproduce
Bacteria are larger and can reproduce and live independently
Bacteria also have a nucleus and cytoplasm whilst viruses do not
How large is a typical virus?
~100nm
Describe a virus
Basic protein coat with either RNA or DNA inside
How do viruses reproduce?
Attaching to a host cell membrane and injecting their DNA/RNA which the host cell will replicate thus producing more viruses. When the host cell becomes full of virus, it ruptures and the thousands of virus search for new host cells.
Why are viral infections harder to target ?
Vary fast rate or reproduction (very spread before symptoms are present)
Simpler biochemical structures
May lie dormant for periods
Rapid replication leads to high mutation rates
What do vaccines do?
Help the body produce antibodies against viruses
What does amantadine do?
Inhibits an enzyme in the flu virus which doesn’t allow the virus to stick to a host cell
What does acyclovir do?
Has a similar structure to deoxyguanosine and thus can be mistaken for viral DNA but will terminate DNA synthesis
Describe an amine group
R-N-R
(where R is variable)
Describe an amide group
R-C(=O)-N(-R)-R
(where R is variable)
Name two antacids
Omeprazole
Ranitidine
What molecules can form hydrogen bonds?
N, O, F
Name two antivirals
Oseltamivir
Zanamivir
Name a less polar antiviral
Oseltamivir
Name a more soluble antiviral
Zanamivir
Define retrovirus
Has RNA instead of DNA
What is HIV/AIDS?
A human retrovirus which attacks the T-helper cells
Describe the life-cycle of an HIV virus
HIV virus infects a host cell and releases reverse transcriptase which is used by the human cell uses to synthesise RNA from DNA
This then passes into the nucleus and replicates with the cells own DNA during replication making thousands of new HIV virus
What does AZT do?
It’s an anti-retroviral used against HIV as it inhibits reverse transcriptase
What are the problems when fighting HIV/AIDS?
T helper cells (which form part of the immune system) are destroyed weakening the immune system
The virus can lay dormant for years 10 on average)
Rapid replication can lead to mutations
How many enantiomers are produced from SN1?
2
How many enantiomers are produced from SN2
1
What is a chiral centre?
A carbon with 4 different groups attached
What was the original use of Thalidomide?
Anti-morning sickness drug
What was the problem with Thalidomide?
One enantiomer was harmless and the other produced dangerous side effects
What kind of mixture is usually produced under lab conditions of an SN2 reaction?
Racemic mixture
(with a 1:1 ratio of each enantiomer)
How can we most efficiently prevent the production of the more harmful enantiomer?
Using a chiral auxillary
What is a chiral auxillary?
A chiral molecule which binds to the reactant, physically blocking one of the reaction sites by steric hinderance meaning that the reaction can only occur on the other side
Which drug has 11 chiral centres?
Taxol
What is taxol used to treat?
Breast, ovary and brain tumours
How does taxol work?
Inhibits mitosis by preventing breakdown of microtubules
Where can taxol be found naturally?
Pacific Yew Tree
Describe a phenyl group
Benzene ring
Describe an ester group
(C=O)O
Describe a ketone group
R-(C=O)-R
Describe a hydroxyl
C-OH
Describe a heterocycle
Any ring where one of the corners is not a carbon
Describe an alkene
C=C
What are the two functions of radioisotopes in chemistry?
Diagnostic
Treatment (to kill cancer cells)
Give examples of side effects of nuclear medicine
Hair loss
Nausea
Fatigue
Loss of appetite
Damage to healthy cells
Sterility
What are tracers?
Isotopes used to follow a path through the body
What is the half life of Tc-99
6 hours
What are the properties of isotopes?
Same chemical properties as other isotopes
Different physical properties
What encompasses physical properties of a molecule?
Melting point
Boiling point
Density
Colour
What encompasses chemical properties of a molecule?
How they react and which reactions they undergo
What kind of radiation do tracers emit?
Gamma
Give examples of a tracer molecules?
Tc-99
I-131
What is the risk of using tracers?
Still ionising to a degree and therefore still a risk of cancer
What are gamma rays?
Photons of light
What beta particles?
e-
What are alpha particles?
Helium nucleus (2 protons, 2 neutrons)
What is TAT?
Targeted alpha therapy
How can alpha particles be useful?
Very high ionisation at short distance so can be put into a tumour and kill only the cells around it
What is a nuclear equation?
The equation to show the decay of a radioisotope (doesn’t require charge symbols)
Describe BNCT
Boron Neutron Capture Therapy
Boron 10 is injected into a patient and then the patient is irradiated with neuron which are captured by boron which decays and releases an alpha particle
Give the nuclear equation for BNCT
B-10 + n-1 -> B-11 -> Li-7 + He-4
What are the advantages of BNCT?
Very safe
Very localised
How are Lutetium-177 and Ytrium-90 used in radiotherapy?
They are added to the carrier molecule DOTA-TATE (memorise the name) which attaches to tumours and releases radioisotopes to kill the cells
How may potassium dichromate crystals be used to detect alcohol?
Colour change from orange -> green
(as ethanol in the body is converted to ethanal)
What should be present in a normal breath?
O2, N2, CO2, H2O
How does an infrared intoximeter work?
Passes infrared light through a breath sample and compares to a control
If C-H molecules were in the sample the IR light spectrum will be different to the example
What is the problem with the orange->green test with potassium dichromate crystals to test for alcohol consumption?
Very inaccurate
What is the UK legal limit for alcohol?
The legal limit in the UK is 80mg per 100ml sample breathe
How does a fuel cell breathalyser work?
Breathe passes into a cell where it is converted to ethanoic acid and electrons which are detected as an electrical urrent. The higher the current, the greater the amount of alcohol
How does a fuel cell breathalyser work?
Breathe passes into a cell where it is converted to ethanoic acid and electrons which are detected as an electrical current. The higher the current, the greater the amount of alcohol
What methods can be used to identify drugs using spectroscopic methods?
Mass spectroscopy
Infrared spectroscopy
NMR
Chromatography
Distillation
Solvent extraction
Describe mass spectroscopy as a method for identifying drugs
Molecules are broken into fragments and parent ion is used to identify which molecule is present
Describe infrared spectroscopy as a method for identifying drugs
Different bonds vibrate with different energies, the absorption spectrum can be compared to identify which bonds are present
Describe NMR as a method for identifying drugs
Chemical shifts and hydrogen environments and their splitting at different integration values can be used to work out how many different types of hydrogen are in a structure
What is TMS?
Tetramethyl silane
This is used as a control for NMR as it has 1 hydrogen environment in an even polarity
What are the different types of chromatography?
Paper
Thin layer
Column
Gas liquid
High performance liquid
How does chromatography work?
A stationary phase and a mobile phase are used and the mixture of chemicals separates across them as they interact
What is an Rf value?
A value to identify what proportion of the distance travelled by the mobile phase, was also travelled by a single section of the mixture
What type of chromatography is used for alcohol detection?
Gas liquid
How does gas liquid chromatography work?
Urine/ blood is heated and passed through a coiled tube with a liquid layer on the inside. The only thing that will come out the other end is ethanol… idk why?! apparently it’s irrelevant
How can distillation be used to separate chemicals?
Seperate them by boiling point
What is Raoults Law?
P= P(A)X(A) + P(B)X(B)…
Where P(A) is partial pressure of A and X(A) is mole fraction of A
How is mole fraction calculated?
Amount of moles of molecule A / Total moles
How can we ensure distillation is pure?
Do many times, seperating each time, the liquid from the gas
Describe solvent extraction as a method for identifying drugs
Dissolve the sample in a solvent in which it does not mix well thus allowing the different elements to seperate
