Pharmacology/PSA Flashcards
What type of drug is amiloride and what does it do?
Potassium-sparing diuretic used to reduce K+ losses
e.g in patients taking other diuretics
What type of drug is Digoxin and when might it be given
Cardiac glycoside
Rate control drug given in AF (particularly ptx with HF)
What is Bumetanide an example of? Give another?
Loop diuretic
Other- furosemide
What in Indapamide an example of? Give another?
Thiazide-like diuretic
Other= bendroflumethiazide
What is Diltiazem an example of? Give another?
Non-dihydropyridine
Other= verapamil
These are CCBs selective for the heart for rate control
Give an indication for amiodarone?
Rate + Rhythm control in AF
Class and indication for Doxazosin?
Alpha blocker
HTN and BPH
What is the MOA for statins?
Inhibit MHC Co A reductase therefore preventing synthesis of chloesterol
Class, MOA and indication for metoprolol?
Beta blocker (B1 selective)
Reduces force of contraction and speed of electrical conduction
Supraventricular tachycardias, AF (rate control)
Where would you find B1, B2, B3 adrenoceptors?
B1= heart B2= smooth muscle e.g in bronchioles B3= adipose tissue
What are the SEs of statins?
How can we monitor their effect?
Elevated liver enzymes and muscle SEs (myopathy/rhabdomyolysis)
Liver profile measured before statin and after 3 months
If liver transaminase levels >3 times normal limit then stop drugs
Before prescribing statins, which 2 investigations should you consider?
Liver profile- to monitor potential SEs of statins
TFTs- to detect hypothyroidism- a reversible cause of hyperlipidaemia
What is contained within an Epipen? When and how should you administer it?
300mg adrenaline
IM anterolateral thigh, held for 10 seconds
Note cartridge contains 2mg adrenaline in 1mg/1ml solution so only 0.3ml actually injected
Fluticasone is an example of what drug?
Inhaled corticosteroid
Hycosine butylbromide is an example of what? When is it indicated?
Antimuscarinic
1st line pharmacological tx of IBS (anti-motility)
palliative drug to reduce copious resp secretions
Which class of drug should non-dihydropyridines e.g verapamil NOT be prescribed with? What happens if they are?
Beta-blockers
Cause heart block, cardiogenic shock, asystole
What is meant by third-degree heart block?
Transmission between atria and ventricles is completely blocked, they now beat independently
What goes in the medicines reconciliation section on a hospital drugs chart?
Drugs that patients were taking prior to admission
Who told you
Any changes made on admission
What is meant by patient-specific direction?
Written instructions, From independent prescriber (e.g doctor) For a medicine to be supplied/administered To a named patient Assessed on an individual basis
(hospital prescription must be accompanied by entry in medical records)
How does obtaining consent for prescriptions on a hospital ward work?
Assumed consent on hospital wards
Seek consent if high risk of adverse effects or off-license use of drug
What information should be written about a medicine when prescribing it on a hospital chart?
Name of generic medicine Route Form Strength Timing / Frequency Start and stop date (+/- review date) Other relevant information
When might you prescribe a branded drug over a generic drug?
Generic drug has different available release forms e.g oxycodone (generic): oxynorm= immediate release, oxycontin= modified release
Combination products- brand name contains mix of products, easier than prescribing individual drugs
Drug has narrow therapeutic index
Which abbreviations are acceptable for hospital prescriptions?
Kg, g, mg
L, ml
What are the following routes abbreviations:
PO, IV, IM, SC, SL, PR, PV, NG, INH, TOP
PO= oral. IV= intravenous. IM= intramuscular. SC= subcutaneous. SL=sublingual. PR= per rectum. NG= nasogastric. INH= inhaled. TOP= topical
What is meant by the following abbreviations relevant to prescribing:
PEG, PEJ, NG, NJ, LE. RE, BE, IA, SC pump
PEG= via PEG (percutaneous endoscopic gastrostomy) PEJ= via PEJ (percutaneous endoscopic jejunostomy) NG= nasosgastric. NJ= nasojejunal. LE= left eye. RE= right eye. BE= both eyes. IA= intraarticular. SC pump= via subcutaneous pump.
The patient is unconscious when they arrive at hospital but their relative informs you they are allergic to penicillin. What 3 things should you do?
Document allergy on drugs chart
Record on patient ID bracelet (may be colour-coded)
Alert nurse for nurse-led caring records
VTE assessments are required for all patients admitted to hospital over what age?
All patients over 18 admitted to hospital should have VTE assessment completed.
What are 3 potential outcomes of a VTE assessment?
Low VTE risk- no prophylaxis
Significant VTE risk which outweighs risk of bleeding = prescribe LMWH
Significant VTW risk but with significant risk of bleeding e.g post-surgery= graduated compression stockings
Give 4 examples of when you might prescribe a ‘once only’ medication?
Drugs to be given stat
Pre-surgery single medication
Loading dose of medication given prior to prescribing daily maintenance dose
Vaccines
4 things you may consider when making prescriptions for chilldren?
Form- some children can’t take tablets/capsules
Route- IM usually avoided because painful
Timing- may need adapting around school day
Taste- important to children, influences adherence
In addition to the usual requirements e.g name, dose, strength etc. what extra information should you write in a prescription for a PRN drug?
maximum daily dose
maximum frequency of administration
minimum interval between doses
What class of drug is tiotropium and how does it work?
Long-acting anti-muscarinic bronchodilator
Inhibits PNS stimulation which usually causes bronchoconstriction
What type of drug is fluticasone and give a SE?
Inhaled corticosteroid
SE: oral thrush
Give 1st and 2nd line pharmacological treatment options for depression?
1st= SSRIs e.g fluoxetine/citalopram 2nd= TCAs (amitriptyline), alpha2 adrenoceptor antagonists (mirtazipine)
!!!May need checking (understand 2nd line)
Patient presents to hospital with status epilepticus.
What is 1st, 2nd and 3rd line management of this sitaution?
1st= lorazepam 4mg slow IV (or diazepam) 2nd= If uncontrolled= add phenytoin / valproate 3rd= If uncontrolled= anaesthetise, manage in CCU
What class of drug is Naproxen?
NSAID
Give 3 examples of dug classes which lower seizure threshold?
antidepressants, antipsychotics, opioids (particularly tramadol)
Cyclizine and Ondasentron are both what type of drugs? Give respective MOA.
Anti-emetics
Cyclizine= histamine 1 receptor anatagonist
Ondasentron= serotonin 5=HT3 receptor antagonist
Neuroleptic malignant syndrome is precipitated by drugs with what effect? Give examples
Anti-dopaminergic drugs
Phenothiazine antiemetic e.g. prochlorperazine, chlorperazine
Dopamine antagonist emetics e.g. metoclopromide
Antipschotics e.g, haloperidol
What type of bacteria is Helicobacter pylori?
Gram negative
What is the treatment for Helicobacter pylori peptic ulcer?
PAC (PPI, Amoxicillin, Clarithromycin)
If one of abx CI replace with metronidazole (must always be a triple therapy)
Loperamide is an opioid. What makes it different from other opioids? What is its MOA?
Does not cross BBB so no CNS effects (does not sedate)
Opioid U receptor agonist in myenteric plexus of GI tract therefore anti-motility drug
Prescribed in diarrhoea
Lactulose is an osmotic laxative. When would you prescribe lactulose?
Hepatic encaphalopathy (regardless of constipation) MOA: reduced absotption of ammonia by increasing speed of stool passage and acidifyingh stools therefore inhibiting proliferation of ammonia-producing bacteria
Give an example of a 1st and 2nd generation anti-histamine? What is their difference? Which would be better to prescribe for itch in liver disease?
1st= chlorphenamine. SE- sedative. 2nd= loratadine. X BBB so not sedative
Loratadine preferable for managing itch caused by liver disease as sedation can cause hepatic encephalopathy
What are the adverse effects that the following drugs can have on the liver? Flucloxacillin Paracteamol Methotrexate Statin
Flucloxacillin= rare SE choletatic jaundice Paracetamol= overdose- hepatoceullar necrosis Methotrexate= overdose/hypersensitivity reaction= hepatitis Statins= elevated transaminases, rare- drug-induced hepatitis
A patient currently on regular furosemide starts to develop hypokalaemia. Which medication change could resolve this?
Change to co-amilofruse (furosemide and amiloride- potassium sparing diuretic)
What serum K+ level defines severe hypokalaemia?
<2.5mmol/L
this warrants IV treatment
Give an example of an appropriate IV treatment for hypokalaemia and justify
KCl 20mmol/L in 1L Na+Cl- 0.9% given IV over 2 hours
IV potassium administration should not exceed 10mmol/hr
What class of drug is oxybutinin and what is its indication?
Antimuscarinic (M3 receptor)
Overactive bladder
Where are nicotinic receptors found?
Ach receptors found at NMJ in skeletal muscle
Give 5 examples of drugs which can cause raised K+?
Potassium supplements (oral/IV) Aldosterone-receptor antagonist (spironolactone) Potassium-sparing diuretic (amiloride) ACEi, ARB
(less significantly- aspirin , BBlocker)
What class of drug is solifenacin? Indication? SEs?
Antimuscarinic
Urgency/Urge incontinence
SEs: dry mouth, blurred vision, constipation, confusion
(same as oxybutinin)
Give 5 SEs of beta blockers
Bronchospasm (CI WITH ASTHMA!) ED Fatigue Headache GI upset
Several antibiotics are cleared by the kidney and therefore patients with severe renal impairment required dose reduction to prevent complications.
Give an example of such a drug and it’s potential complication for the 3 classes below:
Penicillins
Tetracyclines
Aminoglycosides
Penicillins= benzylpenicillin/ co-amoxiclav
Comp- CNS toxicity, fits
Tetracyclines= doxycycline Comp= hepatotoxicity, nephrotoxicity
Aminoglycosides= gentamicin Comp= ototoxicity, nephrotoxicity
What is meant by FiO2?
Fraction of inspired oxygen, e.g air =0.21 (21% oxygen)
What are the 2 broad categories of oxygen therapy? Give examples of each?
Controlled O2 therapy= venturi mask
Uncontrolled O2 therapy= nasal cannulae, simple face mask (rebreathe), non-rebreather+resevoir, AMBU bag
When would you consider using a venturi mask?
Worried about patients with CO2 retention
When you need to know FiO2 delivered
What are the 5 different levels of FiO2 oxygen delivery avaialble from a venturi mask?
24% 28% 35% 40% 60%
What is the consequence of under-prescribing oxygen?
Hypoxia- T1RF
What is the consequence of over-prescribing oxygen?
In ptx with chronic hypercapnia, hypoxia is main respiratory driver. Giving O2 removes respiratory drive therefore causing T2RF.
What might you see on ABG which may indicate that a patient is a chronic hypercapnic?
Raised HCO3-
Which patients are at risk of T2RF if over-oxygenated?
COPD
NMJ disorder- MG
Drug overdoses- respiratory depressants e.g opiods/benzos
Severe chest deformity- kyphoscoliosis, ank spond
What are the target ranges for oxygen sats:
Most patients
Ptx at risk of T2RF
Most patients: 94-98%
Risk of T2RF: 88-92%
When might oxygen sats be falsely high?
Carbon monoxide poisoning
Oxygen dissociates from oxyhaemoglobin more easily under what circumstances?
Increased temperature
Increased H+ (acidic)
Increased CO2
(therefore when tissues are hypoxic and therefore acidic, they receive oxygen more easily_
Give 3 potential sites for ABG sampling?
Radial, brachial, femoral
Give some indications for Long Term Oxygen Therapy (LTOT)?
COPD Pulmonary Hypertension Obstructive Sleep Apnoea NMJ disorder Heart Failure Interstitial Lung Disease Lung Cancer
What is the criteria for ABGs to warrant LTOT?
2 ABGs > 3 wks apart not less than 4 wks from exacerbation:
PO2<7.3 kPa
or
PO2 <8kPa + 2nd polycythaemia/ PH/ nocturnal hypoxaemia / peripheral oedema
Give 3 forms of home oxygen therapy, purpose and a major risk to be aware of
Long term oxygen therapy- must be on >15hrs/day
Short-burst O2 therapy- intermittent O2 for exacerbations SOB
Ambulatory O2- O2 cylinder for ptx temporarily away from usual supply
Warning: major fire risk if ptx smokes around oxygen. Ptx should be non/ex smoker before considered for home O2
Patient has a PE,
What investigation and oxygen should they receive?
!!
ABG
High flow O2
Low flow through a non-rebreather turns it into…
a rebreather
What is Senna and how does it work?
stimulant laxative
irritant to gut, increases water and electrolyte secretion from colon mucosa
Give 3 examples of drugs that can precipitate gout?
Thiazide-like diuretics- reduces uric acid secretion by kidneys
Anti-cancer drugs - increased uric acid production with tumour breakdown
Low-dose aspirin
(alcohol too)
What medication is given as long term prophylaxis for gout? MOA?
Allopurinol (xanthine oxidase inhibitor)
MOA methotrexate?
Dihydrofolate reductase enzyme inhibitor
This enzyme usually converts folic acid to FH4
FH4 is required for DNA and protein synthesis
Mx of methotrexate overdose/toxicity?
Folinic acid
Readily coverted to FH4 without the need for dihydrofolate reductase enzyme (which is inhibited by methotrexate)
Which anticoagulant should be prescribed for…
VTE prophylaxis
Established VTE
Prevent arterial thromboembolism
VTE prophylaxis= LMWH e.g dalteparin 5000 units sc
Established VTE= warfarin/ DOAC
Prevent arterial thromboembolism= aspirin
What is the difference between LMWH and unfractioned heparin? Give an indication for LMWH and a circumstance when you might use UF > LMWH?
Unfractioned heparin has shorter duration of activity,
LMWH have longer duration of activity
LMWH more widely used e.g prevention and treatment of DVT/PE
UF used if high risk of bleeding as effects can be terminated rapidly by stopping infusion
UF > LMWH in renal impairment
(BNF- parenteral anticoagulants-2021)
What class of drug is cefotaxime?
cephalospirn
Warfarin is metabolised by CYp450 enzyme. Give an example of a seizure medication that induces and one that inhibits CYP450 and what the resultant effect on prescribing with warfarin is?
Carbamazepine= CYP450 inducer
Increases warfarin metabolism, lower levels of warfarin, greater chance of clotting, lower INR
Valproate= CYP450 inhibitor
Decreases warfarin metabolism, more warfarin, greater chance of bleeding, higher INR
3 medications which can be used first line for uncomplicated UTI and when CI?
Trimethoprim- CI first trimester pregnancy
Nitrofurantoin- CI latter stages pregnancy
Amoxicillin
Medication which can be used 2nd line uncomplicated / 1st line complicated UTI?
ciprofloxacin
What class of drug is ciprofloxacin?
quinolone
2 common bacterial causes of skin/soft tissue infections? 2 antibiotics which may be given?
Skin/soft tissue infection:
Staph aureus, group A strep (strep pyogenes)
Abx- benzylpenicillin, flucloxacillin
Name a penicillinase resistant abx
Flucloxacillin
2 abx given in management of severe penumonia
amoxicillin and clarithormycin (cover typical and atypical microbes respectively)
Patient has an intracranial infection. Pending LP diagnosis which 2 medications should be given?
Cefotaxime- ?bacterial meningitis
Acyclovir- ?viral encephalitis
Patient has suspected intra-abdominal sepsis, which 2 abx should be prescribed?
Metronidazole and co-amoxiclav (covers anaerobic and gram neg aerobic organisms respectively)
What are the components of co-amoxiclav?
Amoxicillin and clavulonic acid
Gove a gram positive and gram negative cause of community acquired pneumonia?
Gram + strep pneumoniae
Gram - haemophilus influenzae
Why might prescribing doxycycline be sensible for unknown cause of community acquired pneumonia?
Doxycycline covers gram +, gram - and atypical bacteria
Which bacteria is flucloxacillin most effective against?
Staph aureus
In what circumstances might you prescribe vancomycin?
infections resistant to penicillins e.g MRSA
C.Diff if recurrent or metronidazole CI
Give 2 examples of antibiotic that may cause ototoxicity and their associated class?
Gentamicin, vancomycin,
Glycopeptide abx
(note that the similar named azithomycin/clarithromycin etc. are macrolides)
What is a potential side effect of tetracyclines and hence who should they not be prescribed to?
Bind to calcium in developing teeth/bones causi discolouration and hypoplasia of tooth enamel/developing skeleton
CI- pregnancy, breast feeding, children <12
What is QT? What is prolonged QT time? Give 4 drugs which cause prolonged QT?
QT= beginning of Q to end of T (time for ventricles to repolarise) Prolonged= >0.44 (M), >0.46 (F) Drugs= antiarrhythitic (amiodarone), antipsychotics (haloperidol), macrolides (clarithromycin), quinnine
Gentamicin, Vancomycin and Clarithromycin should all be given as slow IV infusions.
If they are given as bolus what happens?
Gentamicin- ototoxicity
Vancomycin- anaphylactoid reaction
Clarithromycin- phlebitis/arrythmia
What is phlebitis?
Inflammation of a vein
What is an anaphylactoid reaction- sx? How is it different to anaphylaxis?
Histamine mediated reaction, sx include urticaria, angiodema, bronchospasm
Unlike anaphylais it does not involve IgE antibodies
What are maintenance water, Na+, K+ requirements?
Water 30ml/kg/day
Na+ 1mmol/kg/day
K+ 1mmol/kg/day
What is an appropriate fluid choice for fluid resuscitation?
NaCl 0.9% 500ml over 10mins IV
Concentration of Na+ similar to that in ECF so is retained in ECF. After distribution ~20% remains in circulation.
What is another name for Hartmanns solution?
Compound sodium lactate
Hartmanns is a good option for fluid resuscitation, give the quantity, route and time for this?
Which patients is it inappropriate for and why?
250/500ml IV over 15 mins
Contains K+ (balanced salt solution), so don’t give to ptx with hyperkalaemia/anuria
Glucose 5% is good for fluid replacement but bad for fluid resuscitation, why?
Distributes throughout the entire body leaving only 7% in circulation
Human albumin solution is a colloid solution. Why is it not often used?
Little evidence to suggest colloids > crystalloids
More expensive
Not usually stocked on general wards
What is an appropriate crystalloid / colloid fluid challenge?
Name 2 possible solutions, quantity, route, time?
Crystalloid:
0.9% NaCl / Hartmann’s
250-500ml IV over 15 mins
Colloid:
Human albumin solution / synthetic colloid
100-250ml IV over 15 mins
What is pethidine and when is it typically given?
Opiate analgesia, given IM
particularly given during childbirth
Flumazenil reverses the action of which drug?
Benzodiazepines
Name a rapid acting insulin?
Novorapid
act-rapid is short-acting
Name a short-acting insulin
Actrapid
Name a long-acting insulin
Insulin detemir / Insulin glargine
Most insulins are manufactured to what unit/ml strength?
100 units/ml
Patient glucose recordings indicate that they experience hyperglycaemia overnight and in morning but have better daytime control, what kind of insulin regimen is appropriate in this specific case?
Intermediate-acting insulin given at night before bed
Describe what a basal-bolus insulin regimen involves?
Intermediate/long-acting basal insulin to deliver constant insulin throughout the day, short-acting insulin bolus injections before each meal
What is an advantage of basal-bolus insulin regimen?
Mimics normal pattern of insulin production
More flexibility over meal times
What is a disadvantage of a basal-bolus insulin regimen?
More injections, more monitoring throughout day
What are the indications for giving a continous SC insulin infusion pump?
T1DM >12yo
Ptx experiencing disabling hypos from trying to achieve target HbA1c
HbA1c >61 despite daily injection and good level of care
What should be present on an insulin prescription?
Date,
Route (IV/SC)
Name- brand and generic in full + “insulin”
SC- dose, units, administration device
IV- rate of administration
Always write “units” in full
What equipment should you prescribe for diabetes patients
Monitoring:
Lancet for finger pricking
Blood testing meter (GP / DM clinic only)
Treating:
Syringe if insulin in vials
Injection pens + needles + needle clipping device
Sharps bin
