MP321 Class Test Deck

What is the difference between intrinsic and acquired resistance in bacteria?

• intrinsic = the bacteria is already like that

• Acquired = It acquires the immunity either through horizontal or vertical transfer

Why are gram negative bacteria harder to treat?

• because they have porins that only let small hydrophilic molecules go through

• antibiotics e.g. amoxicillin are broad spectrum if they can go through the porin to reach the inner cell

• Insert pic slide 6

What is an example of intrinsic resistance using gram negative bacteria and vancomycin antibacterial (glycopeptide)?

• vancomycin is big and hydrophilic (insert pic slide 7)

• Hydrophilic molecules can go through porins but vancomycin isn’t small enough to go through

• This is intrinsic as there isn’t anything that can be done to change this and the bacteria didn’t do anything to cause this resistance

What is vertical transfer (acquired resistance)?

(Insert pic slide 8)

• go from non-resistant pool of bacteria to a resistant pool of bacteria (think like a family tree)

• Mother → daughter cells

What are the 3 methods of horizontal transfer (acquired resistance)?

• From daughter → other cells

• transformation - mutant bacteria dies and its free genetic info gets transferred to another cell → other cell receives the resistant mutation

• Conjugation - close contact between cells results in plasmid being transferred → resistant mutation is transferred

• Transduction - viruses called bacteriophages replicate inside the bacterial cell, virus takes some of the genetic info and transfers it to another cell → mutation is transferred using the bacteriophage as a vector

• (Insert pic slide 9)

What are other ways that a bacterial cell is antimicrobial resistant?

• effflux pumps, beta-lactamase produced, changes in structure of porins, enzymes that can alter antibacterials so that they stop working

• (Insert pic slide 10)

What bacteria are part of ESKAPE?

Which one is gram positive?

• enterococcus faecium, staphylococcus aureus, klebsiella, acinetobacter, pseudomonas aeruginosa, eneterobacter

• Staphylococcus aureus

What is a problem with bacteria?

• Keep mutating to become more resistant to more types of antibiotics so harder to treat

What does metallo-beta-lactamase (NDM1) degrade?

So what can treat it?

• penicillins, cephalosporins and carbapenems

• only monobactams

What does metallic-beta-lactamase (KPC) degrade?

What can be used to treat?

• penicillins, cephalosporins, monobactams and cabapenems

• Nothing → WERE FUCKED

What patients are at risk of infection?

• immunocompromised

• In intensive care or post operation

• Malnourished

• Cancer/diabetes

• Elderly or infirm

• Infants

What is bactericidal and bacteriostatic?

• bactericidal = kills the bacteria

• Bacteriostatic = immobilising the bacteria without killing them

How long should IV therapy be used for before you switch to oral therapy?

• IV when you can’t control the infection and switch to oral therapy when patient is back within range

Why are doses in BNF different from doses used in practice for antibiotics?

• would be too expensive for a clinical trial and because a lot of antibiotics have existed for a long time a lot of the doses that were originally in the BNF have since changed

What dose of penicillin is used in practice?

What dose of gentamicin is used in practice?

• 500mg to 1g QTD

• 5-7mg/kg

When should patient be monitored when they have infection?

• throughout treatment not just after they have finished course

• Safety net e.g. - if feel worse come back etc.

What are 80% of pharyngitis cases caused by?

What bacteria causes pharyngitis (other 20%)?

• viral (Will get better itself)

• Streptococcus pyogenes

What can cause otitis media and how can it be treated?

What is important for management of otitis media?

• mostly viral so self limiting

• If bacterial caused by haemophilus influenzae→ amoxicillin, clarithromycin if penicillin allergy

• Pain management as pressure build up in ear = ouch

What are the 3 symptoms for COPD patients where 2/3 need to be met for patient to be treated with antimicrobials?

• increased sputum volume

• Increased shortness of breath

• Purulent sputum

What patients cannot be given doxycycline and why?

What is a side efffect of doxycycline?

• any patient under 12 because the medication affects bones

• Causes photosensitivity

What should non-severe community acquired pneumonia (CAP) be treated with?

What is CURB-65 score for non-severe?

• Amoxicillin, doxycycline, clarithromycin

• 0-1

What should severe community acquired pneumonia (CAP) be treated with?

What is CURB-65 score for severe?

If patient is confused what bacteria is likely to have caused CAP?

• macrolide and penicillin, or penicillin with beta lactamase

• >3

• Legionella

What should not be given to pregnant people with UTI?

Why?

What trimester is it safer to use this drug?

• trimethroprim

• is teratogenic as can affect folic levels → spina biffida

• In the 3rd trimester

What is cellulitis caused by?

What antibiotic?

• s. Aureus or strep pyogenes

• A narrow spectrum penicillin, if MRSA then vancomycin

What is treatment for necrotising fasciitis?

What causes necrotising fasciitis?

• IV antibiotics to hold the infection back but surgery required to get rid of fascia that has been infected

• strep pyogenes

When is the only time that vancomycin can be given orally?

Why?

• when patient has a C diff infection

• Vancomycin doesn’t enter the bloodstream from the GI so normally isn’t a good thing, but because C diff is in the GI its actually a good thing as the vancomycin stays at the site of infection

What are the main choices of dosage form?

• oral/rectal administration

• IV/IM administration

What are advantages and disadvantages of oral administration?

• simplest, convenient and safest means of drug administration

• Potentially irregular absorption of certain drugs

What is main advantages capsules have over tablets?

• drug released faster using capsules than tablets

• Shell that masks taste of drug (some tablets have but not all)

What are disadvantages of tablets?

• poor bioavailability of some drugs

• Local irritant effects to the GI mucosa

What are advantages and disadvantage of powder formulations (oral)?

• faster dissolution rate than tablets or capsules

• not suitable for the administration of drugs which are inactivated in the stomach (same as with capsules)

• Less convenient to self administer

What are advantages and disadvantages of suspensions?

• convenient when drug is not soluble in water and when non-aqueous solvent cannot be used

Disadvantages = risk of sedimentation

What is phenoxymethylpenicillin used to treat?

• tonsillitis, otitis, rheumatic fever

What can be used to treat invasive aspergillosis?

• tablet = voriconazole, suspension = posaconazole

What can amoxicillin be used to treat?

• Lyme disease, h.pylori infection

What can tetracycline be used to treat?

• acne

What are advantages of rectal formulations?

• Good for drugs that get inactivated in GI when taken orally

• Good route when patient is vomiting

• Fast systemic response

What are disadvantages of rectal administration?

• less patient compliance

• Irregular drug absorption

What can be injected intravenously?

• only solutions

What are differences between injections and infusions

• injections are sterile solutions, emulsions or suspensions in water or non-aqueous liquid, injected in less than 15 mins

• Infusions are aqueous solutions that are administered in large volumes 100-1000ml and are injected in more than 15 mins

What are depot preparations?

Where are they injected and what quantity?

What are pros/cons of depot preparations?

• dispersion of the drug in an oily vehicle

• Injected IM and max 5ml at a time into a large muscle to decrease pain and swelling

• Slow release of the drug but can be quite painful

What are the components present in fungizone?

• Amphotericin (polyene) and sodium deoxycholate (surfactant)

What is the problem with fungizone?

• severe side effects

  • Renal toxicity

  • Haemotological toxicity

  • Cardiovascular toxicity

How does fungizone work to cause therapeutic effect?

Why does it result in toxicity?

• Amphotericin binds to ergosterol presents in fungal cell = therapeutic effect

• Toxicity because also targets cholesterol in mammalian cells

• So non-specific/ not selective

Where is ambisome drug located in the liposome?

• located within the liposome membrane (insert pic slide 30)

Why is ambisome better than fungizone?

• passive targeting of the liposomes to the infected organs

• Minimal exposure to non-target tissues (so don’t target mammalian cells)

What is structural differences between fungizone and ambisome in terms of targeting tissue and toxicity?

• for ambisome the Amphotericin stays encapsulated in liposome (lipid bilayer) so less toxic effects and better at targeting just fungal cells and not mammalian cells

• Fungizone, the Amphotericin leaks out of the micelle so it enters circulation, targets both fungal and mammalian cells = toxic effect

How much more toxic is fungizone than ambisome?

What is the main drawback of ambisome?

• 80 times more toxic

• Way more expensive than fungizone ( £24 vs £821) per vial

What are the main choice of dosage form for mild infections?

• topical administration

• (Sometimes oral/rectal administration - dependant)

What is an ideal anti-microbial formulation?

• effective against the targeted infection

• Able to reach site of infection

• Rapid onset and controllable duration

• Free of undesirable side-effects

When is it that oral/rectal administration of a drug would occur when treating a mild infection?

• if infection is more difficult to treat or is spreading fast

What is the advantage of topical administration?

What is the main barrier to this method of drug delivery?

• results in location action

• The stratum corneum (outermost layer of skin)

  • Composed of 15-20 layers of flattened, keratinised cells that must be crossed in order for drug to cause effect

What are the requirements for a suitable drug for topical administration?

• have a low MW (less than 500 Daltons)

• Moderately lipophilic logP between 1-4

• Be effective at a low dose (less than 10mg/day)

Why do topical administrations need to have a lipophilicity between 1 and 4?

• lipophilic enough to be able to penetrate the stratum corneum

• If not lipophilic enough will not penetrate, too lipophilic and will stay in the stratum corneum and not travel to site of infection

What is Fick’s Law of Diffusion?

J = -D triangle C/triangle x

J = flux

D= diffusion co-efficient

C = concentration of diffusing drug

X = distance

What are the formulation types of topical administrations?

• liquid formulations

• Semi-solid formulations

• Solid formulations

What is the advantages and disadvantages of liquid topical formulations?

• Precise as can be applied directly to site of infection

• Evaporation of the solvent leads to cool, soothing effect (good for treatment of acne)

• poor residence time on skin

• Low drug delivery

What are advantages of semi solid topical formulations?

• Good patient acceptance and compliance

• More viscous due to drug being in semi-solid base so good residence time on skin

What type of medication is liquid topical formulations?

• single phase solutions and lotions (e.g. erythromycin solution and clindamycin lotion)

What are bases of semi-solid formulations?

• hydrophobic bases = liquid paraffin, glycerides, waxes

• Hydrophilic bases = polyethyleneglycol (PEG)

What drug types are semi-solid formulations?

• ointments, creams and gels

What are ointments?

What are advantages of ointments?

• hydrophobic, fatty preparations (extra lipophilic base)

• highly occlusive, increase of transdermal drug flux, prolonged drug delivery

• messy to use

What sort of lesions are ointments used for?

• dry, flaky lesions e.g. impetigo (fusidic acid)

What are gels made of?

What is advantage of gels?

• made up of a solution that gets excipients added to it to form a more viscous gel (excipients = PEG, polymers, gums)

• Due to evaporation of alcohols, results in a soothing effect - relief for inflammation

What type of gel provides relief for patients with rosacea?

• metronidazole gel

What are creams?

• made of 2 phased emulsion: either water based tablet dispersed in oil phase or oil based tablet disperse in water phase

What are advantages and disadvantages of creams?

• w/o emulsions less greasy than ointments, easier to apply than ointments, can be washed off the skin surface

• less occlusive than ointments, less beneficial in treating dry skin conditions

What type of formulation are spray powders?

What is an example of a spray powder drug and what is it used for?

• solid formulations

• Miconazole nitrate - treats athlete foot

What is the nail made of?

So what component does the drug need to have?

Why is nail lacquer considered a solid formulation?

• hard keratinised structure

• Keratolytic components (e.g. urea) to increase diffusion of drug through the nail plate (think like is like)

• Because it is a solution that dries to become a solid

What are barriers to drug absorption in the eyes?

• formulation must be sterile, eyes blink and have tears so a lot of the drug gets removed from the eyes

What does homogenous mean in terms of drug formulations?

• means that it is uniformly made so 1 drop would have the same quantity of each component as another drop (and every other drop)

What is a common viscosity enhancer used to make eye drops?

• polyvinylalcohol

What excipients are used to make eye ointments?

• petrolatum, lanolin

What are advantages of using eye ointments?

What are disadvantages of eye ointments?

• reduce drug removal caused by tears and blinking

• Increase of corneal residence time

• Sustained drug release

• more difficult to administer than solutions

• More variable administered dose (not as homogenous)

• causes blurring of vision

• Patients don’t like to comply when it comes to any sort of thing going in eye

What are pessaries and ovules?

• vaginal suppositories = pessaries

• Vaginal capsules, shell pessaries = ovules

• are both solid, single-dose formulations that are ovoid in shape but ovules are more elongated and larger in size

What are advantages and disadvantages to vaginal delivery route?

• treatment of local infections requires lower dose than with oral administration

• No need of absorption of drugs for local action

• release of the drugs influenced by vaginal fluids

What does MCR stand for?

• my chemic… medicines care review

What service did MCR replace?

• CMS (chronic medication service)

What is the main aim of MCR?

• to support people with long-term conditions in managing their medicines effectively (normally people who take multiple meds but not always)

Who is eligible for MCR?

How many pharmacies can the patient choose to register to?

• patients registered with a Scottish GP who take regular long term medication

• only one

What is a serial Rx?

How long can they  last for?

• a prescription issued by the GP

• 24, 48 or 56 weeks

What are the main components of MCR?

• medication review

• care plan

• serial prescriptions

What is the benefit of a serial Rx (for a patient)?

• don’t need to go to GP to get a new prescription every time, and can get it directly from the pharmacy you are registered to

What info is required from patient to sign them up for MCR service?

• name

• dob

• address AND postcode

• gender

• CHI number

What additional things does patient need to confirm before they are part of MCR service?

• they want to register for MCR service (so basically agreement/consent)

• have a long-term condition

• agree doctor and pharmacist can share info about meds

What year was the Humans Medicines Regulations put into play?

• 2012

What section/part of the Humans Medicines Regulations 2012 is “dealings with medicinal products”?

• part 12

When can pharmacists refuse to provide service/supply to a patient?

• if believe Rx if forged

• where supplying to the patient is contrary to the pharmacist’s clinical judgement

• where pharmacist or other on premises are subject to or threatened with violence

• if person with Rx commits or threatens to commit a criminal offense

• where irregularities or deficiencies in a repeat dispensing service mean that a repeat supply isn’t appropriate

What does it mean to be on the pharmaceutical list?

• list of pharmacies approved to provide NHS services 

• Rx written by NHS can only be dispensed by a pharmacy on this list

What kind of pharmacies are allowed to supply NHS Rx?

• only pharmacies included in pharmaceutical list

What happens if a pharmaceutical list pharmacy is given an Rx by a pharmacy not on the list (e.g. private pharmacy)?

• are not allowed to dispense it as it goes against NHS rules

What does a pharmacist supply if no quantity is provided on an Rx?

• up to a 5 day supply

• or supply minimum pack size

What does “supply of products listed in Schedule 10” mean under the NHS Medical Services Regulations?

• It refers to a blacklist of items that must not be supplied or reimbursed under the NHS in Scotland. These products are excluded due to limited clinical or cost-effectiveness. NHS pharmacies cannot dispense these items for NHS payment.

What must a pharmacy do about opening hours?

• display the opening hours and MUST BE OPEN during the opening hours

What year were IP pharmacists legally implemented?

• in 2006 (doesn’t mean all pharmacists became IP’s tho obvi)

What is the “Patient Rights Act” 2011?

• aims to improve patient’s experiences using health services and to support people to become more involved in their health and healthcare

What is the “Equality Act” 2010?

• 116 legislations combined to make new act that provides a legal framework to protect the rights of individuals and advance equality of opportunity for all

What is the “Human Rights Act” 1999?

• lets you defend your rights in UK courts and compel public organisations - including gov, police and local councils - to treat everyone equally, with fairness, dignity and respect

What is the “Data Protection Act” and when was it legislated?

• access to patient data should be monitored and inappropriate usage = penalty (basically respecting confidentiality)

• 2018