Drugs Affecting Cardiovascular System (Blood Pressure)

Question 1

What is the definition of hypertension?

Answer 1

Blood pressure greater than 140/90

Question 2

What does hypertension predispose you to?

Answer 2

stroke, TIA, myocardial infarction, ischaemic heart disease, aortic aneurism, retinal haemorrhage, renal failure

Question 3

What are the risk factors for high blood pressure?

Answer 3

smoking, diet, weight, stress

Question 4

How can BP be reduced without any drug intervention?

Answer 4

By reducing risk factors - smoking, alcohol, fats, salt, BMI and increasing exercise and relaxation

Question 5

How does the sympathetic nervous system influence blood pressure?

Answer 5

By targeting alpha 1 adrenoceptors on arteries to cause vasoconstriction and beta 1 adrenoceptros on the heart to cause increase in heart rate and contractility and beta 1 adrenoceptors on the kidney to increase angiotensin II

Question 6

What is the effect of the kidney on blood pressure?

Answer 6

Stimulation by the sympathetic nervous system causes increase in angiotensin II, angiotensin causes vasoconstriction, increase in aldosterone (water retention), cardiac cell growth and also feedbacks on the sympathetic nervous system

Question 7

How does the renin angiotensin system work?

Answer 7

Renin converts angiotensinogen to angiotensin I and angiotensin converting enzyme converts angiotensin I to angiotensin II

Question 8

What are the five classes of antihypertensive drugs?

Answer 8

Angiotensin system inhibitors, beta-adrenoceptor antagonists, calcium channel blockers, diuretics, other

Question 9

What are the names for ACE inhibitors?

Answer 9

‘prils’ - captopril, enalapril, perindopril, ramipril

Question 10

What is the action of ACE inhibitors?

Answer 10

Blocks conversion of angiotensin I to angiotensin II and also prevents bradykinin breakdown

Question 11

What is the result of ACE inhibitors?

Answer 11

Reduced vascular tone, reduced aldosterone production, reduced cardiac hypertrophy

Question 12

What are the adverse effects of ACE inhibitors?

Answer 12

first dose hypotension, dry cough, loss of taste, hyperkalaemia, acute renal failure, itching, foetal malformations

Question 13

What are the contraindication in ACE inhibitors?

Answer 13

pregnancy, bilateral renal stenosis, angioneurotic oedema

Question 14

What are the names for angiotensin receptor antagonists?

Answer 14

‘sartans’ - losartan, candesartan

Question 15

What is the action of angiotensin receptor antagonists?

Answer 15

Blocks angiotensin receptors AT1

Question 16

What is the result of angiotensin receptor antagonists?

Answer 16

Reduce vasoconstriction, reduce aldosterone, reduce cardiac hypertrophy, reduce sympathetic activity

Question 17

What are the adverse effects of angiotensin receptor antagonists?

Answer 17

hyperkalaemia, headaches, diziness

Question 18

What are the contraindications for angiotensin receptor antagonists?

Answer 18

Same as ACE inhibitors - pregnancy, bilateral renal stenosis, angioneurotic oedema

Question 19

What are the names for beta adrenoceptor antagonists?

Answer 19

‘olols’ - propranolol, timolol (non selective) atenolol, metropolol (selective for beta 1), pindolol (partial agonist for beta 1 and beta 2)

Question 20

What is the action of beta adrenoceptor antagonists?

Answer 20

Blocks beta adrenoceptors on the heart and kidney

Question 21

What is the result of beta adrenoceptor antagonists?

Answer 21

reduced heart rate, reduced heart contractility, reduced renin release (reduces blood volume and TPR)

Question 22

How do different beta adrenoceptor antagonists vary?

Answer 22

Different selectivity for beta 1 or beta 2 receptors, different sympathomimetic activity, different lipid solubility

Question 23

What are the adverse effects of beta adrenoceptor antagonists?

Answer 23

cold extremities, fatigue, dreams, insomnia, bronchoconstriction

Question 24

Why do beta blockers cause cold extremities?

Answer 24

because of reflex alpha-1 arenoceptor constriction and blockade of dilatory beta-2 adrenoceptors

Question 25

Why do beta blockers cause fatigue?

Answer 25

reduced cardiac response and beta 2 blockade of skeletal muscle blood vessels

Question 26

Why do beta blockers causes dreams and insomnia?

Answer 26

Depends on lipid solubility and whether they can pass the blood brain barrier

Question 27

Why do beta blockers cause bronchoconstriction?

Answer 27

Because of beta-2 adrenoceptor blockade in airway smooth muscle

Question 28

What are the contraindications for beta blockers?

Answer 28

diabetes, asthma, atrioventricular block (and care with heart failure and metabolic syndrome)

Question 29

What are the names of calcium channel blockers?

Answer 29

verapamil, diltiazem, felodipine, nifedepine

Question 30

What is the action of calcium channel blockers?

Answer 30

inhibits voltage gated L-type calcium channels in myocardium and vasculature

Question 31

What is the result of calcium channel blockers?

Answer 31

reduces cardiac and vascular muscle contractility

Question 32

What is the difference between the calcium channel blockers?

Answer 32

different selectivity for cardiac or vascular muscle - verapamil effects both, diltiazem is more selective for vascular muscle and felodipine and nifedepine are completely selective for vascular muscle

Question 33

What are the adverse effects of verapamil and diltiazem?

Answer 33

oedema, flushing, headache, bradycardia

Question 34

What are the adverse effects of felodipine and nifedepine?

Answer 34

oedema, flushing, headache, reflex tachycardia

Question 35

What are the actions of thiazide diuretics?

Answer 35

inhibits sodium/cholride cotransporter in distal tubule to decrease sodium cholride reabsorption

Question 36

What is the result of thiazide diuretics?

Answer 36

increases water and sodium excretion to lower blood volume and decrease blood pressure

Question 37

What are the adverse effects of thiazide diuretics?

Answer 37

potassium loss, gout, hyperglycaemia, allergic reaction