4. Pharmacology - Ana Oliviera Flashcards
Define:
- Pharmacokinetics
2. Pharmacodynamics
- What our body does to the drug (time course of drug from site of administration to elimination)
- What the drug does to our body
What are the 4 processes of pharmacokinetics?
Absorption
Distribution
Metabolism
Elimination/excretion
Pharmacokinetics
- Define absorption
- What factors need to be considered?
- Bioavailability: what is this and what is the range it is measured in?
- What are the 4 routes of administration?
- Process of transfer of drug from administration into general/systemic circulation
- Lipid solubility/disintegration/solubility/pH/molecular weight/surface area/contact time/interaction/gastric emptying rate/presence of food/alteration in intestinal motility
- Fraction of administered drug that reaches systemic circulation as a parent drug
0-1 - Enteral
Parenteral (IV, IM, subcutaneous)
Mucous membrane (inhalers, sublingual, suppositories)
Transdermal
Pharmacokinetics
- Define distribution
- Define volume of distribution
- What 2 types of drugs are mainly confined to blood and body water compartments?
- What 2 types of drugs are widely distributed to the tissues?
- What other factors effect distribution?
- What factors can increase the fraction of unbound drug?
- Process a compound is transferred from general circulation to other parts of body and tissues
- How widely a drug is distributed between various body fluids and tissues
- Water soluble/highly protein bound drugs
- Lipid soluble/extensive tissue binding drugs
- BBB/ plasma protein barrier
- Renal insufficiency/Low plasma albumin/late pregnancy
Pharmacokinetics
- Define metabolism
- What type of reactions are type 1 reactions?
- What type of reactions are type 2 reactions?
- What factors can affect metabolism?
- drug is chemically altered to facilitate its action or enhance its elimination
- Oxidation/reduction (cytochrome P450 enzymes)
- Conjugation/hydrolysis
- Race/ethnicity/age/gender/pathologies/genetics/stress/temperature/pollution/nutrition/interactions
Pharmacokinetics
- Define excretion
- Name 5 modes of excretion
- What factors effect excretion?
- Drugs/their metabolites are removed from the body
- Renal/biliary/respiratory/dermal/faecal
- Renal blood flow/renal function/glomerular filtration rate/urine flow rate and pH/concentration of drug in plasma/protein binding/size of drug complex/age
Pharmacokinetics
- What is half life?
- What is therapeutic drug monitoring?
- Time required to reduce plasma concentration to half its original value
- Individualised drug dosage by maintaining plasma or blood drug concentrations within a targeted therapeutic range.
Principles of medicine use in elderly
Discuss the following:
1. ADRs
2. Important aspects particular to old people
- Body changes/ Polypharmacy interactions/ compliance and concordance issues
- Altered physiology/ decreased homeostatic functions/ altered pharmacokinetics and pharmacodynamics/ side effects/ ADRs/ polymorbidity/ Polypharmacy/ less compliance
Principles of medicine use in elderly
Discuss the following:
1. Absorption
2. Distribution
- Bioavailability:
Rate/ interactions/ surface area/ intestinal motility/ blood flow
Swallowing difficulties - Regional blood flow:
More transport time/delayed peak concentration/ slower clearance
Plasma protein binding:
Less albumin levels/ less binding/ less total concentration
Lipid solubility
Principles of medicine use in elderly
Discuss the following:
1. Metabolism
2. Elimination
- Less blood flow to liver=less hepatic metabolism=less clearances
Gender/ co-morbidities/ race/ drug interactions/ frailty/ smoking/diet - Renal excretion:
Renal blood flow/ glomerular filtration rate/ urine flow rate/ pH
Principles of medicine use in elderly
Discuss the following:
1. Pharmacodynamics
2. Homeostatic functions
- Changes in receptor sensitivity/ receptor number/ hormone levels
- Less: postural control/ thermoregulation/ reserve of cognitive functions/ immune response/ response to environmental changes
Principles of medicine use in elderly Discuss the following: 1. Falls in elderly 2. Polypharmacy 3. Compliance and concordance
- More than 4 medicines/ sedation/ hypotension/ ototoxicity/ vision disturbances
- Multiple diseases
Drug interactions/ drug-disease interactions/ ADRs - Poor vision/ beliefs and understanding/ impaired cognitive function/ low manual dexterity/ Polypharmacy
Principles of medicine use in elderly
Discuss the following:
Medication review
NO TEARS Need and indication Open questions Tests and monitoring Evidence and guidelines Adverse effects Risk reduction/prevention Simplifications and switches
Antibiotics Interfere with bacterial cell wall 1. Name 3 and give 2 examples of each. 2. Name 4 subtypes of one of them and give 2 examples of each 3. What is their mechanism of action?
- Beta lactams
Glycopeptides (vancomycin and teicoplanin)
Anti-tuberculosis drugs (pyrazinamide and ethambutol) - Beta lactams:
Penicillins (benzylpenicillin, flucloxacillin and amoxicillin)
Carbapenems (imipenem and meropenem)
Cephalosporins (cefadroxil and cefataroline)
Monobactams - Beta lactams: bind to and inhibit penicillin binding proteins (PBPs) = peptidoglycan cross linking effected = weakens wall = cell lysis
Glycopeptides: binds to terminal D-alanine-D alanine at the end of pentapeptide chain in growing bacterial cell wall = blocks glycosidic bonds forming = blocks formation of peptide cross links
Anti-tuberculosis drugs: interferes with cell wall of mycobacteria
Antibiotics
Interfere with bacterial cell wall
1. Resistance and uses for beta lactams? Caution?
2. Resistance and uses for glycopeptides? Caution?
- Beta lactams
Beta-lactamases- hydrolyse beta lactam ring
Carried on gene/chromosome/plasmids
Resistance to resistor= clavulanic acid + tazobactam
Also, dehydropeptidase is an enzyme that can degrade imipenem (a carbapenem) so you have to give it with cilastatin
Carbapenems used in serious infection resistant to other antibiotics
Caution: allergy
- Van A gene = inducible high level resistance to vancomycin and teicoplanin
Van B gene = inducible high level resistance to vancomycin only
Caution: nephrotoxicity
Antibiotics Interfere with protein synthesis 1. Name the 4 and give 2 examples of each. 2. What is their mechanism of action? 3. Bacteriostatic/bactericidal? Each one
- Macrolides (erythromycin and clarithromycin)
Tetracyclines (doxycycline and tetracyclines)
Aminoglycosides (gentamicin and streotomycin)
Chloramphenicol - Macrolides: binds to 50s ribosome unit = blocks chain elongation
Tetracyclines: binds to 30s subunit = aminoacyl tRNA can’t enter acceptor site on ribosome = blocks chain elongation
Amino glycosides: inhibits protein synthesis in cytoplasm- binds to 30s subunit = blocks binding of formylmethionyl-tRNA to ribosome = prevents initiation complexes hence protein synthesis + misreading of mRNA codons
Chloramphenicol: binds to 50s subunit = blocks action on peptidyltransferase hence protein synthesis
Macrolides mainly bacteriostatic
Tetracyclines bacteriostatic
Aminoglycosides bactericidal
Chloramphenicol bacteriostatic
Antibiotics
Interfere with protein synthesis:
1. Resistance and caution for macrolides
2. Resistance and caution for tetracyclines
3. Resistance and caution for amino glycosides
4. Resistance and caution for chloramphenicol
- Macrolides
Resistance uncommon
Caution: interactions - Tetracyclines
Resistance: decrease in uptake or increase in extrusion/ enzymatic inactivation/ producing protein that interferes with tetracycline binding
Caution: phototoxicity/ chelation of metal ions leading to deposition in teeth and bone growth inhibition (don’t use in children)
3. Aminoglycosides Resistance: 1. Aminoglycoside modifying enzyme = inactivation 2. Membrane impermeability = poor access 3. Poor action site affinity Caution: nephrotoxicity and ototoxicity
- Chloramphenicol
Resistance: chloramphenicol acetylation/ can’t bind to ribosomal target
Caution: can effect human mitochondrial ribosomes = dose dependent toxicity to bone marrow
Antibiotics
Interfere with DNA replication
1. Name the 4 and give 2 examples of one of them
2. What is their mechanism of action?
- Quinolones (ciprofloxacin and ofloxacin)
Co-trimoxazole
Nitroimidazoles
Rifampicin - Quinolones: inhibits topoisomerase 2 and 4 = bacterial DNA can’t supercoil/ replicate/ seperate =rapid cell death
Co-trimoxazole: sulfonamides and trimethoprim (synergistic association)
Both act in following pathway: synthesis of tetrahydrofolate
Sulfonamides = structural analogues of PABA = enzyme inhibition
Trimethoprim = inhibits dihydrofolate reductase = enzyme inhibition
Nitroimidazoles: anaerobic organisms have the electron transport chain needed to reduce metronidazole to its active form = toxic to DNA = bactericidal
Rifampicin: binds to DNA dependent RNA polymerase = inhibits mRNA synthesis
Antibiotics
Interfere with DNA replication
1. Resistance and cautions: quinolones
2. Resistance and cautions: co-trimoxazole
3. Resistance and cautions: nitroimidazoles
4. Resistance and cautions: : rifampicin
- Quinolones
Resistance: mutations in gene encoding subunit of DNA gyrase/ ciprofloxacin effluent in some bacteria
Caution: interactions and caution in children - Co-trimoxazole
Resistance: DHF reductase without affinity to trimethoprim
DHT reductase with low affinity to sulfonamides
Caution: 1st trimester of pregnancy - Nitroimidazoles
Resistance: enzyme production = no formation of reactive metabolite
Caution: alcohol - Rifampicin
Resistance: changes in RNA polymerases
Caution: metabolic interactions and orange saliva, tears and sweat
Define agonist and state the 2 types
Binds and stimulates physiological regulatory effects of endogenous compounds
Full/partial
Define antagonist and name the 4 types
Bind but do not have regulatory effects and prevent binding of endogenous compounds
Competitive/non-competitive
Reversible/ irreversible
- Define drug affinity and state what it is numerically
2. Define drug efficacy and state what it is numerically
- How tightly a ligand binds to a receptor
K(small A) - Ability to produce a biological effect
R (small max) or B (small max)
- What is drug potency?
2. What is tolerance?
- Measure of drug activity
2. Gradual decrease in responsiveness to a drug
What are the 4 molecular mechanisms of drug action?
- Direct physiochemical effect
- Effect on transport systems
- Enzymes
- Interaction with a receptor
What are the 2 types of ADR’s and define it
- On-target effects: related to pharmacological action of drug
- Off target effects: unrelated to main pharmacological action of drug
What are the ABCDE types of ADR’s? Explain each one in 1 sentence
A= augmented reactions
Normal dose but exaggerated effect/unwanted reactions predictable from drugs pharmacology
B= bizarre reactions
Not pharmacologically predictable
C= continuing/chronic reactions
Persist for long time
D= delayed reactions
Become apparent some time after use of medicine
E= end of use reactions
Associated with withdrawal of medicine
ADR’s
- Immediate reaction?
- First dose reaction?
- Early reactions?
- Intermediate reactions?
- Late reactions?
- Delayed reactions?
- Give slowly over 1 hour
- Use low first dose
- Introduce drug slowly
- Careful monitoring and dose adjustment
- Use short course when possible
- Avoid in women of child bearing age
Treatment of lipid disorders
- What are the 4 drugs? Give an example of 2 of them.
- What is the mechanism of action of each?
1.resins (cholestyramine)
Ezetemibes
Fibrates (benzafibrate)
Statins
- Resins: bind to bile acid=more gut secretion, reducing its recirculating + reducing absorption of exogenous cholesterol
Less bile acid so more cholesterol broken down (to try and make more bile acids)
Less cholesterol so more LDL receptor expression so IDL removed from circulation
Ezetemibes: act in brush border of intestine = decreased absorption of biliary and dietary cholesterol
Less cholesterol so more hepatic LDL receptor expression
Fibrates: ligand for nuclear transcription factor “PPARalpha” = stimulates lipase activity
Less VLDL production by liver
Less LDL uptake by liver
Reduces TG/ LDL/VLDL
Statins: inhibits HMG-CoA in cholesterol synthesis pathway
Less cholesterol so less synthesis and secretion of lipoproteins from liver
More LDL receptor expression
Pleiotropic effects: antioxidant/ anti inflammatory and angiogenesis
Treatment of lipid disorders
- ADR’s and “avoid in” for resins
- ADR’s and “avoid in” for ezetimibe
- ADR’s and “avoid in” for fibrates
- ADR’s and “avoid in” for statins
- Which one has important interactions are what are they?
- Constipation and reduced absorption of other medications
Avoid in: bowel/biliary obstruction - Rhabdomyolysis if used with statin and GI disturbance
Avoid in: history of hypersensitivity - Rhabdomyolysis if used with statin and GI side effects
Avoid in: hepato-biliary disorders - Rhabdomyolysis/GI disturbances/ insomnia/ rashes and hepato-biliary effects
Avoid in: acute liver disease + pregnancy/breastfeeding - Statins has important interactions due to CYP450
Avoid: antibacterials/antifungals/grapefruit juice
Interacts with anticoagulants/CCB/fibrates
Anti platelets
- What are the 4 drugs? Give 2 examples for 2 of them.
- What is their mechanism of action?
- Aspirin
Dipyridamole
P2Y (ADP) receptor antagonists (clopidogrel and ticagrelor)
GP 2b3a inhibitors (abciximab and tirofiban) - Aspirin: inhibits cox-1 = inhibits TxA2 production by platelets
Also inhibits prostacyclin synthesis
Dipyridamole: phosphodiesterase inhibitor = increases cAMP levels and may stimulate adenylyl cyclase
P2Y (ADP) receptor antagonists: blocks effect of ADP on platelets
GP 2b3a inhibitors: bind to GP 2b3a receptor = blocks binding of fibrinogen and prevents platelet aggregation
Anti platelets
- Uses, 3 ADR’s and 1 “avoid in” for aspirin
- Uses for dipyridamole
- Uses for P2Y (ADP) receptor antagonists
- Uses and 1 route for GP 2b3a inhibitors
- Secondary prevention of MI/prevents events in PVD patients/ cerebralvascular disease
Bleeding/ GI intolerance/ hypersensitivity
Avoid in children (risk of Reye’s syndrome)
2. Prophylaxis of thromboembolism (with warfarin) After TIA (with aspirin)
- For specific indications (with aspirin)
- NSTEMI/ cardiac surgery
IV only
Name the 4 steps of the analgesic leader, stating:
Pain level at each point
What is recommended
Some examples
Also, what is the opioid antagonist called?
- Mild pain (1-3)
Non- opioid analgesics
With/without adjuvant
Paracetamol/NSAIDs - Moderate pain (3-6)
Opioids
With/without non-opioid analgesics and adjuvant
Codeine/tramadol + laxative - Severe pain (7-10)
Opioids
With/without non-opioid analgesics and adjuvant
Morphine/ diamorphine + laxative or antiemetic - Interventional
Blocks/ spinal medications/ surgical procedures
Opioid antagonist= naloxone
Analgesic ladder
Non-opioids: NSAIDs/COXIBs
1. What kind of analgesic effect? What kind of action?
2. What is the mechanism of action?
3. What kind of agent would you give with it?
4. Give 2 examples
- Mainly peripheral
Antipyretic and analgesic and anti-inflammatory action - Competitive inhibitors of cox
Reduces production of prostaglandins - Gastroprotective agent (PPIs/misoprostol)
- Ibuprofen and naproxen
Analgesic ladder
Non-opioids: paracetamol
1. What kind of analgesic effect? What kind of action?
2. What is the mechanism of action?
3. What is it extensively metabolised by?
- Mainly central
Antipyretic and analgesic action - Inhibits cox in brain
- Liver
Analgesic ladder
Weak opioids:
1. What kind of analgesic effect?
2. What 3 types of receptors are involved and which G protein are they coupled to?
3. What are the 3 MOA’s?
4. Name 2 weak opioids and which one has a ceiling dose?
5. Caution in?
6. What should you definitely not do with these drugs?
- Central and peripheral
- Meu, delta and kappa receptors all coupled to Gi proteins
- Inhibit AC=less cAMP so affects phosphorylation pathway
Inhibit voltage gated calcium channel = less NT release
Activates potassium channels = hyperpolarises cell membrane - Codeine and tramadol (codeine has ceiling dose)
- Renal/hepatic impairment and epilepsy
- Don’t “kangaroo”
Analgesic ladder Strong opioids 1. Give an example of 2 2. What does the dose depend on? 3. If the pain is not relieved, what do you increase? 4. How is it excreted? 5. ADR's?
- Morphine and fentanyl
- Precious medications/ age/ general condition
- Increase dose (not frequency)
- Really excreted
- Constipation, N&V, sedation, confusion, respiratory depression, increase intrabiliary pressure, hypotension, bradycardia
Fibrinolytics/ thrombolytics
What are the 4 drugs?
What is their mechanism of action?
Where is each one made?
- Streptokinase
Forms 1:1 complex with plasminogen = which forms plasmin and hence dissolves the clot
Streptococcus - Alteplase
Activates plasminogen bound to fibrin
Recombinant human t-PA - Urokinase
Converts plasminogen to active plasmin
Synthesised by kidney - Anistreplase
Human plasminogen + bacterial streptokinase
Fibrinolytics/ thrombolytics
- What are the 4 uses
- What are the 2 side effects?
- Acute ischaemic stroke
Arterial thrombosis
Venous thrombosis
Acute MI - Bleeding
Allergic reactions
Diarrhoea and constipation
What are the 4 drugs?
What is their mechanism of action?
- Bulk forming laxatives
Retain fluid within stool = increase faecal mass
Stimulate stretch receptors and promote peristalsis - Osmotic laxatives
Draw in fluid and retain water by osmotic effect = increases volume - Stool softeners
Increased penetration of intestinal fluids into faecal mass = less surface tension
Softens stool = promotes defaecation - Stimulant laxatives
Direct stimulation of colonic nerves = promotes propulsive motility
Diarrhoea and constipation
- Time and ADR’s: bulk forming laxatives
- Time and high dose ADRs: osmotic laxatives
- What kind of action: stool softeners
- Time, ADR and avoid in: stimulant laxatives
- Several days
Flatulence, bloating and abdominal distension - 2-3 days
Flatulence, bloating, diarrhoea electrolyte disturbances
3.surfactant action
- 8-12 hours
Abdominal cramp
Avoid in intestinal obstruction
Respiratory drugs
- Name the 2 bronchodilators
- Name the bronchodilator and anti-inflammatory
- Name the 2 anti-inflammatorys
- Beta2 agonists and anti-cholinergics
- Methylxanthines
- Corticosteroids and leuokotrienne receptor antagonists
Respiratory drugs - bronchodilators
Beta2 agonists
1. Which receptor is involved? Which G protein is involved? What are the next 3 compounds activated?
2. This leads to the phosphorylation of what? What is the end result?
3. Name 2
4. Caution due to?
5. ADRs?
1. Beta2 receptor Gs protein AC, cAMP and PKA 2. MLCK bronchodilation 3. Salbutamol and formoterol 4. Tolerance 5. Skeletal muscle tremor/ tachycardias and arrhythmias/ metabolic response/ paradoxical hypoxaemia/hypokalaemia
Respiratory drugs - bronchodilators
Anti-cholinergics
1. Which receptor is involved? Which G protein? What is the next compound that is activated?
2. This allows for the activation of what 2 compounds? What do both of these do? What is the final result?
3. What are anti-cholinergics also known as? So what do they do to this pathway? What does this lead to?
4. Give 2 examples
5. Caution due to?
6. ADRs?
1. Muscarinic receptor Gq protein PLC 2. IP3 = calcium release DAG = PKC activated Both lead to contraction 3. Muscarinic receptor antagonists Inhibit this pathway Relaxation 4. Ipratropium Tiotropium 5. Glaucoma and prostatic Hypertrophy 6. Dry mouth/ blurred vision/ urinary retention/ paradoxical bronchoconstriction/
Respiratory drugs - bronchodilator and anti inflammatory
Methylxanthine
1. What is its MOA that leads to bronchodilation?
2. What is its MOA that leads to anti-inflammatory effects?
3. Give 2 examples
4. Caution due to?
5. ADRs?
- Non-selectively inhibits PDE= inhibits cAMP degradation/metabolism
- Adenosine receptor antagonism = stops it releasing inflammatory neurotransmitter
- Aminophylline
Theophylline - Narrow toxicity - CP450
- Gastrointestinal disturbances/ CNS stimulation/ cardiovascular effects/ hypokalaemia
Respiratory drugs - anti-inflammatory
Corticosteroids
1. It goes into what part of the cell to bind to the receptor? Where does it go to next? What does it do here?
2. It stops the conversion of phospholipids into what?
3. The end result is more of what?
Less of what?
4. Give an example of 3 and state the route of administration
5. ADRs? And with prolonged high doses?
- Cytoplasm
Nucleus
Alters gene transcription - Arachidonic acid and therefore TXAs, LTs and PGs
- More anti-inflammatory molecules
Less cytokines, inflammatory enzymes, PG and LT synthesis - Inhale: beclometasone
IV: hydrocortisone
oral: prednisolone - Oral candidiasis/dysphonia
With prolonged high doses: osteoporosis/ suppression of response to infection/ GI upset/ hypertension/ metabolic effects (cushings syndrome)
Respiratory drugs - anti-inflammatory
Leukotriene receptor antagonists
1. Inhibit leukotriene pathway by inhibiting what?
2. If the pathway was to go on as normal, what would the 2 effects be?
3. Give an example of 2
4. ADRs?
- Leukotriene receptor
- Inflammatory effects (vascular permeability and mucous production)
Bronchoconstriction - Montelukast
Zafirlukast - Headache/ gastrointestinal upset/ hypersensitivity/ dry mouth
Anti-coagulants
Coagulation cascade
1. What are the two starting pathways called?
2. Where do they join? What is the pathway now called?
3. What are the 2 key events in the cascade?
- Intrinsic pathway and extrinsic pathway
- Join at factor Xa to become the common pathway
- Prothrombin converts to thrombin
Fibrinogen converts to fibrin
Anti-coagulants
1. What are the 3 drugs?
What is their MOA
- Unfractionated heparin
Inactivated the activated clotting factors - Low molecular weight heparin
Increases action of AT3 on factor Xa - Warfarin
Acts metabolism of vitamin K
Competitive inhibitor of vitamin k reductase
Inhibits clotting factors 2,7,9 and 10
Anti-coagulants
- Time, uses and ADRs: unfractionated heparin
- 1 example, what is is not neutralised by and uses: low molecular weight heparin
- Metabolism site, uses and ADRs (+ how to overcome this): warfarin
- Immediate action
Thromboprophylaxis/ DVT&PE/ prevents coronary events
Haemorrhage/ thrombocytopenia/ hyperkalaemia/ osteoporosis - Enoxaparin
Protamine
Thromboprophylaxis/ DVT & PE/ prevent coronary events/ MI - Liver (CYP450 system)
DVT & PE/ prevents events in AF/ prevents events in mechanical heart valves
Bleeding based on age/INR/ high BP/ peptic ulcer/ antibiotic use
Give fresh frozen plasma/ clotting factors/ vitamin K
Diuretics
What are the 4 drugs? Give an example of each as well as what to avoid in each case?
- Loop diuretics
Furosemide
Avoid: anuria - Thiazide diuretics
Hydrochlotothiazide
Avoid: electrolyte disturbance and Addison’s disease - Potassium sparing diuretics
Amiloride
Avoid: Avoid: electrolyte disturbance and Addison’s disease and potassium supplements - Aldosterone antagonists
Spironolactone
Avoid: Avoid: electrolyte disturbance and Addison’s disease and potassium supplements
Diuretics: loop diuretics
- Location?
- Time? Administration route? Dosing info?
- MOA: Competes with what?inhibits what?
- 2 uses
- 3 ADRs
- Thick ascending loop of henle
- 6 hours
oral/ IV/ IM
High ceiling effect - Completes for chloride binding site
Inhibits ion co-transporter for sodium/ potassium and chloride - Heart failure + resistant oedema
- Ototoxicity/ hypokalaemia/ hyperglycaemia
Diuretics: thiazide diuretics
- Location?
- Time? Administration route?
- MOA: what does it bind to? What kind of interaction is it?
- 2 uses? Ineffective in what?
- 3 ADRs
- Early distal convoluted tubule
- 12-24 hours
Oral - Bunds to sodium chloride symporter
Competitive antagonism - Heart failure and hypertension
Ineffective in renal impairment - Hypokalaemia/ hyperglycaemia/ hyperuricaemia
Diuretics: potassium sparing diuretics
- Location?
- Administration route?
- MOA: binds to and blocks what in the luminal membrane? This increases the excretion of which 3 ions? This decreases the excretion of which ion?
- Use?
- 2 ADRs
- Late distal convoluted tubule
- Oral
- Binds to and blocks sodium channels in the luminal membrane
Increases excretion of sodium/ chloride/ water
Decreases excretion of potassium - Preventing hypokalaemia (with other diuretics)
- Hyperkalaemia/ metabolic acidosis
Diuretics: aldosterone antagonists
- Location?
- Administration route?
- MOA: blocks what kind of receptors? This reduces the synthesis of which 2 things? Which ion channel permeability does it also reduce?
- 2 uses
- 3 ADRs
- Late distal convoluted tubule
- Oral
- Blocks cytoplasmic receptors
Reduces synthesis of sodium potassium ATPase and sodium channels
Also reduces sodium channel permeability - Ascites and heart failure
- Impotence/ menstrual disturbances/ gynaecomastia
Cardiovascular drugs
- What are the 4 steps of treating someone under 55 years of age?
- What are the 4 steps of treating someone over 55/black person of African or Caribbean family origin?
- Describe the steps of the RAAS system pathway
- Ace-I
Ace-I + CCB
Ace-I + CCB + Th D
Ace-I + CCB + D + alpha/beta blocker - CCB
CCB + Ace-I
CCB + Ace-I + Th D
CCB + Ace-I + D + alpha/beta blocker - Angiotensinogen/ (renin) / angiotensin 1 / (ACE) / angiotensin 2 / angiotensin 2 receptors /
AT 1 subtype/ aldosterone
AT 2 subtype
Cardiovascular drugs
- Name the 4 drugs and give 2 examples of each (for one of them you will need to give 3)
- What is their MOA?
- Ace inhibitors
Ramipril + captopril
Angiotensin receptor antagonists
Losartan + valsartan
Calcium channel blockers
Dihydropyridines: nifedipine + amlodipine
Non-dihydropyridines: verapamil
alpha blockers
Doxazosin + indoramin
- ACE-I: inhibits ACE
AT receptor antagonists: block AT receptor so AT2 can’t be converted into AT 2 receptors. This effects the AT-1 subtype
CCB: binds to alpha 1 receptor on L type voltage gated calcium channel. Blocks calcium influx into heart and arterial blood vessels
Alpha blockers: binds to alpha receptor which is linked to Gq protein. So this can’t activate PLC which won’t allow activation of IP3 (so no calcium release so no contraction) and won’t allow activation of DAG (so no PKC so no contraction)
Cardiovascular drugs
- Effect + ADRs + contraindications: Ace inhibitors
- Effects + ADRs: AT receptor antagonists
- Effects + uses: CCB - dihydropyridines
- Effects + Uses + drug interactions: CCB - non-dihydropyridines
- ADRs: CCB
- Effect + uses + ADRs: alpha blockers
- Arteriovenous vasodilation / reduced vascular resistance / reduced blood pressure
ADRs: dry cough/ hyperkalaemia/ renal insufficiency
Contraindications: hyperkalaemia/ renal artery stenosis/ hypersensitivity - Arteriovenous vasodilation/ reduced vascular resistance/ reduced blood pressure
ADRs: no dry cough - Vasodilation (more specific for calcium channels in vascular smooth muscle)
Hypertension + angina - Vasodilation / acts on myocardium + AV node and SA node
Hypertension + angina + supraventricular arrythmias
Drug interaction: beta blockers - Flushing / headaches/ ankle oedema
- Vasodilation
Hypertension/ benign prostatic hypertrophy
ADRs: postural hypotension/ dizziness/ fatigue
