drugs Flashcards
1
Q
ARDs of Losartan?
A
-
Drug class
- angiotensin receptor blocker
- Acts on chymases (act on ATII independently of the RAAS pathway)
-
Common indications
- Diabetic nephropathy I type 2 diabetes
- Chronic heart failure (when side effects with ACEi)
- Hypertension - reduces risk of stroke inputs w hypertension and left ventricular hypertrophy
- Hypertension with intravascular volume depletion
-
Mechanisms of action
- reversible and competitively prevents angiotensin 2 binding to the AT1 receptor
-
Important adverse drug reactions we discussed
- abdo pain
- Hypotension
- Postural hypotension
- Nasuea
- Dizziess
- Headache
- Hyperkalaemia
- Retail impairment
- Vertigo
- Vomitting
-
Important drug-drug interactions
- combination of ATII receptor antagonist with aliskiren (renin inhibitor) is contra indication inpatients with DM - when together it increases the risk of renal impairment
- NSAIDs
- Alcohol
- Drugs that increase potassium
2
Q
ARDs of Indapamide?
A
-
Drug class
- thiazide like diuretic
-
Common indication
- hypertension
- At lower doses its more prominent in diuretics. The diuresis effect becomes are apparent with higher doses/
-
Mechanism of action
- Inhibits the sodium chloride co transporter therefore less is reabsorbed and more water is excreted into the urine.
-
Important adverse drug reactions
- hyperglycaemia, erectile dysfunction, increased LDL and TG, hypercalcaemia, hypokalemia, hyperuricaemia, electrolyte imbalance, fatigue, headache, constipation/diarrhoea, vomitting, postural hypotension, nausea
-
Important drug-drug interactions
- alcohol - can both increase the risk of hypotension
- Amplodipin - can increase the risk of hypotension
- Aceclofenac - increase the risk of acute renal failure
- Allopurinol - increase the risk of hypersensitivity reactions when given with idapamide
- Amfampridine, amiodarone, amisulpride - cause hypokalaemia
- Contraindicated if history of hypersensitivity to sulfonamides
-
Why is the drug taken as a single dose in the morning?
- if taken too late in the day, you might have to get up during the night to go to the toilet
3
Q
ARDs of amlodipine?
A
-
drug class
- calcium channel blocker - dihydropyridine
-
Common indications
- hypertension, angina,
-
Mechanism of action
- Blocks L type calcium channels, prevents Ca2+ entering cells and therefore stops smooth cell contraction → relaxation and vasodilation.
- It’s selective for peripheral vascular use uses therefore on,y targets BVs
-
Important adverse drug reactions
- abdo pain, dizziness, drowsiness, flushing, headache, nausea, palpitations, peripheral oedema, skin reactions, tachycardia, vomitting
-
Important drug-drug interactions
- alcohol - increase risk of hypotension
- Simvastatin - amlodipine increases the effect of the stating
-
Contraindicated in
- unstable angine
- Severe aortic stenosis (bc CO is already low)
-
Tissue region and selectivity of the drug and why it’s important when it comes to its therapeutic use?
- Because it’s peripheral
4
Q
ARDs of Atorvastatin?
A
- drug class
- statins
- common indications
- Primary hypercholesterolaemia in patients who haven’t responded adequately to diet and other measures
- heterozygous and homozygous familial hypercholesterolaemia in patients who haven’t responded adequately to diet and other measures
- primary prevention of cardiovascular events in pts at high risk of a first cardiovascular event
- secondary prevention of cardiovascular events
- mechanism of action
- they competitively inhibit HMG CoA reductase which is an enzyme involved in cholesterol synthesis esp in the liver
- therefore can’t make cholesterol.
- as cholesterol is then low, LDLs will be taken up to distribute cholesterol to cells - decreasing the cholesterol levels, decreases the chances of a CV event
- important adverse drug reactions
- arthralgia (joint stiffness), asthenia (weakness, lack of energy and strength), memory loss, pancreatitis, paraesthesia, sexual dysfunction, skin reactions, vomiting
- important drug-drug interactions
- Acipimox - increases the risk of rhabdomyolosis when given with this drug
- alcohol - increase the risk of hepatotoxicity
- aprepitant - increase the exposure of atorvastatin (monitor and adjust dose)
- amlodipine - effect of atorvastatin increased
- macrolides, amiodarone - ABs increase the effect of statins
- contraindicated
- pregnancy, hepatic or renal failure, breastfeeding
5
Q
Spironolactone
A
- drug class
- aldosterone receptor antagonist
- potassium sparing diuretic
- common indications
- resistant hypertension
- moderate to severe heart failure
- oedema in congestive heart failure
- nephrotic syndrome
- malignant ascites
- oedema
- ascites in cirrhosis of the lier
- mechanism of action
- antagonist of aldosterone, therefore stops the production of aldosterone at the CD so sodium isn’t reabsorbed via EnaC and is excreted with water.
- Potassium isn’t pumped via ROMK therefore this drug is potassium sparing
- important adverse drug reactions
- hyperkalaemia
- gynaecomastia
- acute kidney injury
- electrolyte imbalance
- GI disorder
- malaise
- nausea
- confusion/dizziness
- important drug-drug interactions
- other drugs that are potassium sparing/potassium increasing drugs
- alcohol - can increase the risk of hypotension
- amiloride - they can both increase the risk of hyponatraemia and hyperkalaemia
- amlodipine - increase risk of hypotension
- ACEi and ARBS
- contraindications
- pregnancy
- renal and hepatic disease
- hyperkalaemia
- addisons disease - because they already have an adrenal hormone shortage including aldosterone
6
Q
Verapamil
A
- drug class
- Class IV anti-arrhythmic
- Calcium channel blocker
- common indications
- angina
- Supraventricular Arrhythmia
- Hypertension
- Mechanism of action
- stops calcium entry therefore affects the plateau phase of ventricular AP- less steep slope so slower heart rate
- Separates/depresses SA node and slow AV conduction therefore negative inotropy
- Important adverse drug reactions
- constipation
- Bradycardia
- Heart block
- Cardiac failure
- Palpitations
- Important drug-drug interactions
- beta blockers
- Other anti hypertensive and anti arrhythmic drugs
- Contraindications
- Poor liver function
- AV nodal conduction delay
- atrial flutter or fibrillation associated with accessory conducting pathways (e.g. Wolff-Parkinson-White-syndrome
7
Q
Amiodarone
A
- drug class
- class III antiarrhythmic
- common indications
- arrhythmias, esp when other drugs are ineffective or contraindicated
- arrhythmias associated with wolf parkinson white syndrome
- ventricular fibrillation or pulseless ventricular tachycardia refractor to defibrillation
- mechanism of action
- block potassium channels
- increases action potential duration
- prolongs phase 3 and refractory period
- prevents early after depolarisations
- slows down heart
- important adverse drug reactions
Restrictive pathology- pulmonary fibrosis, hepatic injury, increase LDL, thyroid disease, photosensitivity, optic neuritis
- arrhythmias, hepatic disorders, hyperthyroidism, nausea, respiratory disorders, skin reactions
- important drug-drug interactions
- amiodarone has a long half life so there is potential for drug interactions to occur for several weeks (or even months) after treatment has been stopped
- digoxin
- warfarin
- atenolol
- biaoprolol
- contraindications
- avoid in severe conduction disturbances (unless pacemaker is fitted)
- severe resp failure
- severe arterial hypotension
- unusual pharmacokinetics and why it is contraindicated in thyroid disease
- can lead to the inhibition of T4 and T3 entry into the peripheral tissues
- It contains iodine - therefore can causes hyper/hypothyroidism
8
Q
Ezetimibe
A
- drug class
- cholesterol absorption inhibitor
- common indications
- primary hypercholesterolaemia - if statin inappropriate or not tolerated
- Hyperlipidaemia
- mechanism of action
- inhibits NPC1L1 transporter at brush border in small intestines
- reduces absorption of cholesterol by the gut
- Hepatic LDL receptor expression increases → decrease total cholesterol and LDL
- it’s a pro drug - relies on hepatic metabolism to be converted to active form - it undergoes enterohepatic circulation → limits systemic exposure so it stays locally
- secreted by bile
- important adverse drug reactions
- abdominal pain, GI upset, angioedema, headache, asthenia
- important drug-drug interactions
- mindful if prescribed with statin - theoretical increased risk of rhabdomyolysis
- contraindications
- hepatic failure
- pregnancy - only give if benefits>risks
- administration of drug !!!
given in single dose
9
Q
Dapagliflozin
A
- Drug class
- SGLT-2 inhibitors - gliflozins (urine flows out)
- Common indications
- T2DM - as mono therapy if metformin inappropriate
- T2DM - in combination with insulin or other antidiabetic drug
- Mechanism of action
- decrease glucose absorption from tubular filtrate in PCT, increases urinary glucose excretion
- Important adverse drug reactions
- UTI (because glucose retention), genital infection, polydipsia and polyuria, pancreatitis?
- Important drug-drug interactions
- Antihypertensive and other hypoglycaemic agents
- Contraindications/warnings
- hypovolaemia - possible hypotension
- Avoid initiation if eGFR < 15mL/min
- Consider additional antidiabetic drug with dapagliflozin if eGFR < 45mL/min
10
Q
Clopidogrel
A
- drug class
- ADP receptor antagonist
- Common indications
- Prevention of atherothrombotic regents in percutaneous coronary intervention (adjunct w/aspirin) in patients not already on clopidogrel
- Transient/acute ischaemic attack for patients with aspirin hypersensitivity, or those intolerant fo aspirin despite the addition of a proton pump inhibitor
- Mechanism of action
- inhibits binding of ADP to P2Y12 receptor → inhibits the activation of GPIIb/IIIa receptors (independent of COX pathway)
- Important adverse drug reactions
- bleeding, GI upset - dyspepsia and diarrhoea, haemorrhage, skin reactions
- Rarely - thrombocytopenia
- Important drug-drug interactions
- clopidogrel requires CYPs for activation so - bc it’s a pro drug
- Any CYP inhibitors - omeprazole, cirpofloxacin, erthromycin, some SSRIs
- Need to consider the use of other PPIs with clopidogrel
- Caution when co prescribes with other antiplatelet and anticoagulants or NSAIDs - increased bleeding risk
- Contraindications
- Caution in high bleed risk patients with renal/hepatic impairment
- Avoid in pregnancy
- Discontinue 7 days before elective surgery
- Careful in elderly - who have significant bleeding risk, such as uncontrolled severe hypertension, bleeding diathesis or recent non-trivial spontaneous bleeding
- How if differs to other drugs with the same mechanism of action?
- compared to ticagrelor and prasugrel, clopidogrel has a slow onset of action without a loading dose - there’s some inter-individual variability in antiplatelet action
11
Q
Semaglutide
A
- drug class
- Glucagon like peptide 1 receptor agonist (incretin mimetics)
- common indications
- Type 2 DM as mono therapy (if metformin inappropriate) or in combo with other antidiabetic drug incl insulin if existing treatment fails to achieve adequate glycaemic control
- Mechanism of action and route of administration
- subcutaneous injection
- It binds to and activates the GLP-1 receptor to increase insulin secretion, suppress glucagon secretion and slow gastric emptying
- Resistant to degradation but DPP-4 because they’re modified components
- Important adverse drug reactions
- GI upset, decreased appetite with weight loss
- Warnings - renal impairment
- Important drug-drug interactions
- other hypoglycaemic drugs
12
Q
Flecainide
A
- drug class
- Sodium channel blocker - class 1c
- Anti arrhythmic
- Common indications
- supraventricular arrhythmia (fibrillation and flute)
- Ventricular arrhythmia
- Wolff Parkinson white syndrome
- Mechanism of action
- acts to increase the refractory period, slower depolarisation of cardiac cells and slow heart rate
- Increase APD (k+)
- Decrease automaticity (increase threshold)
- AP shifts to right and doing this multiple times to try and reestablish sinus rhythm
- common adverse effects
- Arrhythmia, asthenia, dizziness, dyspnoea, fever, oedema, vision disorders
- ‘flecainide flutter’ - increase ventricular response to supraventricular arrhythmias
- Common drug-drug interactions
amiodarone increases the concentration of flecainide
13
Q
Aspirin
A
- drug class
- Cyclo-oxygenase inhibitor (COX1)
- Common indications
- some AF patients post stroke
- Secondary prevention of stroke and TIA
- Secondary prevention of stroke and TIA
- Post primary percutaneous coronary intervention and stent to reduce ischaemic complications
- Often co prescribed with other antiplatelet agents
- NSTEMI/STEMI - chewable is best
- GI protection requires for long term use in at risk patients (proton pump inhibitor)
- Mechanism of action
- it inhibits COX-1 mediated production of TXA2 and reduced platelet aggregation - irreversible
- common adverse drug reactions
- GI irritation, GI bleeding (peptic ulcer), haemorrhage (stroke), hypersensitivity, dyspepsia
- common drug-drug interactions
- Other antiplatelet and anticoagulants (additive/synergistic action)
- Reye’s syndrome - avoid <16 years, avoid if breastfeeding: regular uses of high doses could impair platelet function and produce hypothrombinaemia in infant if neonatal vitamin K stores are low
- Reyes = Permanent brain and over damage - can cause seizures and fits
- But can give to kids who have Kawasaki disease
- Hypersensitivity
- 3rd trimester - premature closure of ductus arteriosus
14
Q
Celecoxib
A
- drug class
- Selective COX 2 inhibitor
- Selective - to avoid GI side effects (but there still are risks of GI side effects)
- Common indications
- pain and inflammation in OA, rheumatoid arthritis, ankylosing spondylitis
- Mechanism of action
- blocks COX2 therefore inhibits PGI2
- Avoids inhibition of homeostatic actions mediated by COX 1
- Common adverse side effects (come back pls)
- Increased risk of MI (bc stops platelet aggregation)
- GI (less ? to COX 1 inhibitor?) and renal effects
- Common drug-drug interactions
- Aciclovir - increase risk of nephrotoxicity
- Aspirin - increase risk of bleeding (decrease platelet aggregation)
15
Q
Azathioprine
A
- drug class
- immunosuppressant (non-biologic)
- common drug indications?
- SLE and vasculitis - as maintenance therapy
- RA (weak evidence)
- IBD
- autoimmune conditions
- severe Crohn’s
- other uses as a ‘steroid sparing’ drug
- mechanism of action?
- it’s cleaved into 6-mercaptopurine by TPMT - a metabolite that blocks purine and therefore DNA synthesis so inflammatory cells get inhibited.
- TPMT has a variable expression in different people so have to test TPMT activity before prescribing - if high levels, then the drug will have a high effect
- common adverse reactions?
- bone marrow suppression - monitor FBC
- increased risk of malignancy - esp in transplant patients
- increased risk of infections
- hepatitis - monitor LFTs
- leucopenia
- pancreatitis
- thrombocytopenia
- risk of myelosuppression is increased in patients with reduced activity of the TPMT enzyme
- common drug-drug interactions?
- HPV vaccine, live and influenza vaccine (live) and MMR vaccine (live) - predicted to increase the risk of generalised infection when any of these are given with this drug
- ramipril - increase risk of anaemia/leucopenia
- contraindications?
when used for severe refractory eczema - absent TPMT activity
