Cardiovascular / Blood Drugs Flashcards
(124 cards)
1
Q
How do Loop Diuretics work?
A
Inhibit Na+/K+/2Cl- Co-transporter in the loop of henle
So water doesn’t re enter bloodstream with these ions
It also directly improves contractile ability of “overstreched” heart muscle
2
Q
When would a loop diuretic be prescribed?
A
Relieve breathlessness in acute pulmonary oedema (with oxygen and nitrates)
Fluid overload in chronic heart failure
Other oedematous states
3
Q
What other heart failure medicine do you need to be careful with when it is prescribed with Furusemide?
A
Digoxin, increased risk of digoxin toxicity due to diuretic associated hypokalaemia.
4
Q
When wouldn’t you use furosemide?
A
Severe hypovolaemia or dehydration
Caution in those at risk from hepatic encephalopathy
In hypokalaemia / hyponatraemia
5
Q
What side effects would you look out for in someone taking furosemide?
A
dehydration
hypotension
hypomagnaesia, hypocalcaemia, hydrogen loss (alkalosis?)
Hearing loss and tinnitus
6
Q
How is furosemide excreted?
A
In the urine
7
Q
What would you tell a patient before they are started on furosemide?
A
They will go to the toilet more (so don’t take late at night)
Why they are taking it
Its side effects
8
Q
Name a Thiazide diuretic and explain how they work
A
Inhibits Na+/Cl- co-transporter in the distal convoluted tubule. This prevents sodium (and associated water) reabsorbtion.
9
Q
When would a thiazide diuretic be used?
A
Hypertension, first line in children or if in heart failure (i.e. when calcium channel blocker not appropriate). Also as an add on for poorly controlled hypertension
10
Q
When would a thiazide diuretic be less effective?
A
when prescribed with an NSAID (low dose aspirin not a problem)
11
Q
When are thiazide diuretics contraindicated?
A
Hypokalaemia
Hyponatraemia
Gout (increases uric acid concentration)
12
Q
What does contraindicated mean?
A
A situation when the drug in question should not be prescribed
13
Q
Name some side effects of Thiazide like diuretics
A
Potential impotence in men
Hyponatraemia (not usually a problem)
Hypokalaemia (can cause heart arrhythmias)
14
Q
How are thiazide like diuretics eliminated?
A
Rapidly renally
15
Q
Patient info for thiazide like diuretics?
A
Water tablet for high blood pressure
Will make you go to the toilet more
Impotence in men possible
Other side effects
16
Q
What is spirinolactone, and how does it work?
A
Potassium sparing diuretic
Inhibits reabsorbtion of sodium (and therefore water) in distal convoluted tubule
Weak diuretic on its own
17
Q
When would you prescribe spirinolactone?
A
When treating hypokalaemia brought on by loop or thiazide diuretic therapy
18
Q
When wouldn’t you use spirinolactone?
A
When a patient has hyperkalaemia or is on potassium elevating drugs e.g. K+ supplements or aldersterone antagonists.
When someone is volume depleted
When someone has severe renal impairment
19
Q
What are the possible side effects of spirinolactone (all are uncommon)
A
GI upset
Dizziness
Hypotension
Electrolyte disturbances
20
Q
What would you tell a patient before starting them on spirinolactone?
A
To counteract the potassium loss caused by other water tablet.
Will still need the loo a lot!
Drink a lot of water.
21
Q
How does Atenolol (Beta-blocker) work?
A
Reduce the force and speed of contraction of the heart
By binding to Beta-1 receptors on myocardium (Beta-2 mainly in smooth muscle)
22
Q
What effects does the action of beta-blockers have on the cardiovascular system?
A
Relieves cardiac ischaemia by reducing O2 demand
Protect heart in from chronic sympathetic stimulation in HF
Prolongs refractory period, slowing heart rate
Lowers BP by reducing renin secretion by kidneys (medicated by Beta-1 receptors)
23
Q
What drug is first line treatment of angina and acute coronary syndrome?
A
Atenolol
24
Q
When would you use Atenolol?
A
Angina from ischaemic heart disease (first line)
Chronic heart failure (first line)
AF (first line) to reduce rate
Supraventricular tachycardia (SVT) to restore sinus rhythm
Hypertension when other medications insufficient.
25
With what kind of cardiac drug is atenolol contrainidicated due to its interactions?
Non-dihydropyridine calcium channel blockers
26
When are beta blockers contraindicated?
Asthma (bronchospasm) - beta-2 receptors in airway
COPD: use Beta-1 specific drugs eg Atenolol
Heart block
Haemodynamic instability
27
What are some side effects of beta blockers?
Fatigue, cold extremities, headache and GI disturbance common
Sleep disturbance, nightmares!
Rarely impotence in men
28
How is atenolol eliminated?
95% renally
29
What would you tell a patient before starting them on beta-blockers?
To help your heart and cardiovascular system
Side effects
May initially worsen symptoms, but will get better
30
What kind of drug is Ramipril?
ACE (Angiotensin converting enzyme) Inhibitor
31
How do angiotensin converting enzyme inhibitors work?
Block ACE. Stops angiotensin 1 converting to angiotensin 2. (Angiotensin 2 is a vasoconstrictor and promotes aldosterone secretion).
Reduces peripheral resistance, lowering BP
Works especially well in efferent glomerular arteriole, so lowered intraglomerular pressure, slowing CKD
32
What is the suffix of ACE inhibitors?
-pril, e.g. Ramipril
33
When would you use and ACE inhibitor?
Hypertension (first line)
Chronic heart failure (first line)
Ischaemic heart disease
Diabetic neuropathy
34
What drug interactions do ACE inhibitors have?
```
Avoid with potassium elevating eg spirinolactone due to hyperkalaemia risk
Avoid NSAIDS (increases risk of renal failure)
```
35
When are ACE inhibitors / ARBs contraindicated?
Renal artery stenosis of AKI
| Pregnancy, breastfeeding
36
Name some side effects of ACE inhibitors
```
Persistent dry cough
Hypotension (particularly on first dose)
Hyperkalaemia
Can worsen renal failure
Rare: angiodema and anaphylactic
```
37
How are ACE inhibitors / ARBs eliminated?
Renally
38
What would you tell someone starting on ACE inhibitor?
To lower BP
Dry cough, dizziness, rarely anaphylactic
Avoid OTC antiinflammatories (ibuprofen)
Yearly blood tests
39
Name an Angiotensin receptor blocker
Losartan
40
How does Losartan work?
Block angiotensin 2 at AT1 receptor, stopping its effects.
41
Why would losartan be used instead of an ACE inhibitor?
When ACE inhibitor not tolerated (usually due to dry cough)
42
What is losartan used for?
Hypertension
chronic heart failure
ischaemic heart disease
43
When are ARB's contraindicated?
Renal artery stenosis
AKI
pregnantcy / breastfeeding
44
What would you tell someone before starting them on an angiotensin receptor blocker (ARB)?
Replacing ACE inhibitor with this (probably due to cough)
Dizziness possibility
Yearly blood tests
Avoid NSAIDS
45
Name some examples of nitrites
GTN (glyceryl trinitrate)
| isosorbide nitrates
46
What is the mechanism of nitrates?
Converted to NO
NO increased cGMP in vascular smooth muscle cells, relaxing them (vasodilation)
Reduces cardiac preload and left ventricular filling.(reducing work and O2 demand)
Can releive coronary vasospasm and dilate coronary vessels, increasing perfusion
47
Indications of short acting nitrates eg GTN spray?
Acute angina (reperfuse heart)
48
Indications of long acting nitrites eg isosorbide mononitrate?
Angina where beta blocker / calcium channel blocker not effective
49
IV nitrates, along with oxygen and furosemide is used to treat what?
Pulmonary oedema
50
When are nitrates contraindicated?
Severe aortic stenosis, as heart may not be able to cope with vasodilation in vessels further on than the aorta when nitrates reduces preload.
Hypotension
51
Interactions with nitrates?
Must not use with phosphodiesterase inhibitors eg sidenafil as they enhance hypotensive effects of nitrates hugely.
Caution with antihypertensives
52
Name some side effects of nitrates
Flushing, light headedness, hypotension
| Tolerance after prolonged use
53
What would you tell a patient who you prescribe GTN spray to?
Use before tasks which usually bring about angina
Sit down and reat for 5 minutes after taking due to postural hypotension risk
Use to relieve angina
54
`What class of drug is Digoxin?
Cardiac glycoside
55
How does digoxin work? directly and indirectly on myocytes
```
Increases vagal (parasympathetic) tone, reducing contraction from AV node, preventing some impulses being sent to the ventricles, reducing ventricular rate.
Also direct effect on myocytes: inhibit Na+/K+ATPase, causing Na+ to build up in cells. Ca2+ also accumilates because of Na+, increasing contractile force
```
56
Digoxin is used to treat atrial fibrillation and atrial fllutter. What is the difference between these conditions?
In atrial fibrillation, the atria beat irregularly. In atrial flutter, the atria beat regularly, but faster than usual and more often than the ventricles, so you may have four atrial beats to every one ventricular beat.
57
When is digoxin contraindicated?
When there are conduction abnormalities, eg heart block
| Vertricular arrhythmias
58
What drugs interact with digoxin?
Loop and thiazide diuretics increase risk of digoxin toxicity my hypokalaemia
Amioderone, calcium channel blockers, spirinolactone and quinine all increase plasma conc digoxin so greater risk of toxicity
59
Side effects of digoxin?
```
Bradycardia
GI upset
Rash
Dizziness
Visual disturbance
Small theraputic window (monitoring)
```
60
Name a common anti-dysrhythmic that increases the plasma concentration of digoxin
Amioderone
61
What is amioderone's mechanism of action?
Many effects on myocytes eg blocking Na+, K+, Ca2+ channels, antagonising alpha and beta adrenergic receptors. This reduces spontaneous depolarisation, slows conduction velocity and increases resistance to depolarisation. This reduces ventricular rate in AF and atrial flutter.
62
When is amioderone indicated?
Tachicardias: AF, Atrial flutter, SVT, VT,
| Generally only used when other theraputic options unavailable
63
When is amioderone contraindicated?
Heart block
Severe hypotension
Active thyroid disease
64
Side effects of amioderone?
Chronic use: pneumonitis, heart block, AV block, hepatitis, thyroid abnormalities (due to iodene content), photosensitivity
65
What would you tell a patient starting on amioderone?
Having treatment for irregular / fast heart rhythm
side effects
Don't drink grapefruit juice,
Be careful with sun (photosensitivity)
66
What kind of drug is clopidogrel?
Antiplatelet
67
How does clopidogrel work?
PRevents platelet aggregation by binding to adenosine diphosphate (ADP) receptors on the surface of platelets.
Less aggregation -> less arterial occlusion
Action is synergystic with aspirin
68
When is clopidogrel indicated?
```
(Usually with aspirin)
To prevent occlusions in those at risk basically:
Acute coronary syndrome (given rapidly)
Coronary artery stents
Long term prevention in CHD, PVD
```
69
When is clopidogrel contraindicated?
Active bleeding
Elective surgery in next 7 days
Caution in renal / hepatic impairment
70
Give an example of a pro-drug and explain how it works.
clopidogrel
| Requires metabolism by cytochrome p450 enzymes in liver to get into its active form
71
What effect would omeprazole, ciprofloxacin, erythromycin, some ssri's have on clopidogrels efficacy?
Reduce it as these are cytochrome p450 inhibitors
72
Name some side effects on clopidogrel
Bleeding
GI upset
rarely affects platelet numbers as well as function
73
How is clopidogrel eliminated?
50% liver, 50% kidneys
74
What would you say to someone starting clopidogrel?
To reduce risk of strokes, heart attacks and to prolong life.
If bleeding occurs, it can take longer than usual to stop.
Report bleeding to a doctor
75
How do heparins work?
Inhibit thrombin and factos Xa in clotting cascade
| low molecular weight heparins (LMWH) favor Xa
76
When would heparin be indicated?
VTE (LMWL first line vte prophylaxis)
| Acute coronary syndrome (first line to improve revascularisation and prevent intercoronary thrombus progression)
77
When is heparin contraindicated?
```
Bleeding risk! (clotting disorders, severe hypertension, surgery/trauma)
Renal impairment (use unfractionated heparin instead)
```
78
Name one common and one rare side effect of heparin
Bleeding!
| Heparin induced thrombocytopenia (HIT) - Low platelet count and thrombosis
79
How is heparin eliminated?
Renally
80
What effect does warfarin have on the clotting cascade?
It inhibits hepatic production of vitamin K dependant factors : 2, 7 & 9.
Does this by inhibiting vitamin k epoxide reductase
81
When is warfarin indicated?
DVT and PE to prevent clot extension and reoccurenceprevent embolic complications eg stroke in AF & heart valve replacements.
82
When is warfarin contraindicated?
Immidiate risk of haemorrage
Caution in liver disease: less able to metabolise drug so at higher risk of bleeding
Pregnancy: fatal malformations in first trimester
83
How is warfarin metabolised?
How do fluconazole and macrolide antibiotics affect it?
How do phenytoin and carbamazepine effect it?
Cytochrome p450 enzymes in liver
Fluconazole: Cp450 inhibitors so decrease metabolism, more risk of bleeding
Phenytoin: Cp450 inducers, increase metabolism, more risk of clots
84
How is warfarin eliminated?
Metabolites excreted renally
85
How does rivaroxiban work?
Inhibits vitamin k epoxide reductase, preventing production of vitamin k dependant clotting factors (2, 7, 9) in clotting cascade
86
How do statins work?
Inhibit HMGCoA reductase, a liver enzyme involved in cholesterol production
Also increases LDL clearence from the blood
87
When would someone be prescribed statins?
As prevention in cardiovascular disease (qrisk 20%+)
| To treat primary hyperlipdaemia
88
When are statins contraindicated?
Rarely!
Caution in hepatic and renal impairment
Avoid in pregnancy / breastfeeding
89
What reduces statins metabolism?
Cytochrome p450 inhibitors eg Amioderone, macrolides etc
90
What are the side effects of statins, and how common are they?
Rare!
headaches and GI upset
rarely rhabdomyolsis
91
What would tell someone who is starting on a statin?
Prevention for heart attacks and strokes
To lower cholesterol
Seek help if you get muscle pain (rhabdomyolosis)
Avoid grapefruit juice (cytochrome p450)
92
What kind of drug is salbutamol?
Beta-2 agonist
93
How does salbutamol work?
Agonist to receptors in smooth muscles of bronchi, GI tract, blood vessels and uterus. Stimulation starts cascade which results in smooth muscle relaxation
94
When is salbutamol indicated short and long acting?
Short acting to releive breathlessness due to bronchoconstriction eg asthma, exacerbation COPD
Long acting for chronic asthma - always give with corticosteroid.
95
When should you use salbutamol with caution?
Cardiovascular disease, can produce tachycardia - angina
96
Why would someone suffering with angina not have bronchoconstriction adequately controlled?
Angina: on Beta-blocker (eg Atenolol)
| Beta blacker may reduce the effects of salbutamol, a beta2 agonist taken to relieve bronchoconstriction.
97
What would you tell a patient starting salbutamol
To relax airways
Inhaler technique
Take to relieve symptoms, not to treat underlying disease
98
What do anticholinergics / antimuscarinics do?
Bind to muscarinic receptor, competitive inhibitor of acetlycholine
Blocks parasympathetic action of muscarinic receptor activation, reducing smooth muscle tone, increasing heart rate and conduction, reducing secretions in respiratory and GI tracts, pupillary constriction.
99
When would a antimuscarinic be prescribed?
COPD: relax bronchioles, relieving breathlessness and exacerbations
Asthma: short acting help salbutamol in exacerbations, long acting with preventors.
100
When are antimuscarinics contraindicated?
Angle closure glaucoma: emergency! raise in intraoccular pressure
Caution in arrhythmias (most ok with it)
101
Why are there no problems with interactions in antimuscarinics?
low systemic absorption
102
How are anti muscarinics eliminated?
Breathed out!
103
Name a corticosteroid
Prednisolone
104
How do corticosteroids work?(in cells, immunologically, endocrine and electrolyte)
Bind to glucocorticoid receptors on the cell membrane
Translocate into cells and bind to elements which regulate gene expression in the nucleus
Upregulate anti inflammatory genes
Downregulate pro inflammatory genes eg cytokines
Also directly supress circulating monocytes and eosinophils
Increase gluconeogenesis
Stimulate Na+ & water retension, and K+ secretion
105
When would a corticosteroid be prescribed to someone?
Allergic or inflammatory disorders eg anaphylaxis, asthama
Suppress autoimmune disease eg UC, chrons,
Hormone replacement in adrenal insufficiency or hypopituatorism
106
When are corticosteroids contraindicated?
Caution in infected and children
107
Name some interactions of corticosteroids
NSAIDS: increase peptic ulceration
B2 agonists, loop or thiazide diuretics: increase hypokaelamia
Cytochrome p450 inducers: phenytoin, carbemazepine: efficacy reduced
108
What side effects could prednisolone have?
Immunosupression: increased risk of infection
Increased risk of diabetes and osteoporosis
Supress ACTH, so long term use leads to adrenal atrophy
109
What would happen if someone came off prednisolone quickly?
Addisonian crisis: cardiovascular collapse
| withdraw slowly so adrenals can recover
110
How does tissue plasminogen activator (alteplase) work, and what kind of drug is it?
Catalyses plasminogen to plasmin, which acts to dissolve fibrinous clots and recanalise occluded vessels
Fibrinolytic drug
111
Why would you use tissue plasminogen activator?
To re perfuse tissues!
Acute ischaemic stroke
Acute ST elevation myocardial infarction
Massive PE with haemolytic instability.
112
When would it be unsafe to use alteplase?
STROKE- make sure its ischaemic not haemorragic
| In anyone who predisposes to bleeding
113
What does alteplase interact with?
Anticoagulants and antiplatelets
| ACE inhibitors seem to increase the risk of anaphylactic reactions
114
Give some tissue plasminogen activators
Nausea and vomiting
Bruising around injection site
Hypotension
(all nowhere near as bad as their interactions!)
115
What would you tell a patient who si about to be given alteplase
Risks/benefits
1/3 strokes deadly- this will help
Need to do early, ASAP
116
Name an example of a mucolytic drug?
Carbocysteine
117
How does carbosyteine work?
increases sialomucus production, making mucus more viscous and elastic
118
When would carbocysteine be prescribed?
COPD, bronchiectasis
119
Name some side effects of carbocysteine
Dizziness
Diarrhoea
BMs affected
Allergic reaction
120
Name a Theophylline
Theophylline!
121
What does theophylline do?
Relaxes smooth muscles of bronchial airways and reduces airway responses to histamines and allergens
Competitively inhibits phosphodiesterase, which breaks down cAMP in smooth muscle, resulting in bronchodilation.
122
When is theophylline prescribed?
3rd line for reversible airway constriction in asthma, COPD etc
123
Why is it third line?
Due to all its interactions! Loads!
124
In what respiratory condition is oxygen contraindicated and why?
Type 2 respiratory failure
Patients adapt to hypercapnea and hypoxia
Giving O2 upsets balance and can lead to increased blood CO2, leading to respiratory acidosis
