Antihypertensives

Question 1

Name some ACEi

Answer 1

ramipril, Captopril, Enalapril, Lisinopril, Perindopril, Trandolapril.

Question 2

MoA ACEi

Answer 2

competitive inhibitor of angiotensin converting enzyme (ACE)

Inhibits synthesis of potent vasoconstrictor peptide angiotensin II leading to vascular smooth
muscle relaxation and vasodilatation

Overall effect: Reduced blood pressure

Question 3

indications ACEi

Answer 3

 Hypertension (1st line drug in younger caucasian patients <55 years)
 Heart failure and secondary prevention Post-MI
 Type I Diabetic nephropathy
 Following acute MI

Question 4

Dosing ACEi

Answer 4

Starting dose: Hypertension 2.5 mg daily / 1.25mg daily in heartfailure or elderly
Maintenance dose: 10mg daily

Question 5

Adverse effects ACEi COMMON

Answer 5

Persistent dry cough, hyperkalaemia, increase in serum creatinine

(First dose) hypotension – may be profound

Question 6

Adverse effects ACEi important

Answer 6

 Acute renal failure, cholestatic jaundice/hepatitis

 Angioedema, hypersensitivity reactions

Question 7

cautions and contraindications ACEi

Answer 7

caution: anything which could impact renal function wg renal impairment, diuretics

severe aortic stenosis

contraindictaed in pregnancy

Question 8

interactions ACEi

Answer 8

 Diuretics (increased risk of hypotension)
 Potassium sparing diuretics (increased risk of hyperkalaemia) – amiloride, triamterene,
spironolactone, eplerenone
 Potassium salts
 Avoid co-prescription with ARBs candesartan etc. or Direct renin inhibitors – aliskiren
 Lithium
 Immunosuppressants – ciclosporin (increased risk of hyperkalaemia)

Question 9

how do ace inhibitors cause hyperkalaemia

Answer 9

The blockade of angiotensin II prevents the downstream secretion of aldosterone

Question 10

therapeutic drug monitoring ACEi

Answer 10

U&E before and 1-2 w after starting treatment

particularly looking at urea/creatinine and potassium levels for
signs of hyperkalaemia or deterioration in renal function.

Question 11

patient communication ACEi

Answer 11

Explain the need for a blood test (U+E) before starting treatment and 1-2 weeks after treatment.

If
the patient devlops a dry cough within the first few months thenthey should report this to their GP
and their medication will be changed to an ARB.

If the patient is at risk of first dose hypotension (e.g.
elderly) then should take initial first dose at night.

Question 12

name some ARBs

Answer 12

Candesartan, Losartan, Valsartan, Eprosartan,
Olmesartan, Telmisartan, irbesartan

Question 13

MoA ARB

Answer 13

competitive antagonist of angiotensin II AT1 receptor

Selective inhibition of potent vasoconstrictor peptide angiotensin II leading to vascular
smooth muscle relaxation and vasodilatation

Question 14

indications ARBs

Answer 14

 Hypertension
 Heart failure
 Post-MI
 Prevention of cardiovascular events in patients with established atherosclerotic
cardiovascular disease and/or diabetes mellitus with target-organ damage
 Type II diabetic nephropathy

Question 15

medication for diabetic nephropathy

Answer 15

both can have ACEi or ARB but ideal is:

type 1 diabetic - ACEi
type 2 diabetic - ARB (angiotensin 2!)

Question 16

common adverse effects ARB

Answer 16

(First dose) hypotension – less marked than with ACE inhibitor, dizziness, hyperkalaemia,
increase in serum creatinine

Question 17

contraindications and cautions ARB

Answer 17

 Caution in aortic or mitral stenosis and in renal artery stenosis
 Avoid in pregnancy & breast-feeding; do not prescribe to women of child bearing age if they
are trying to conceive.

Question 18

important adverse effects ARB

Answer 18

 Acute renal failure
 Angioedema (may be delayed onset)

Question 19

interactions ARBs

Answer 19

Other antihypertensives (increased hypotensive effect)
 ACE inhibitors, Potassium sparing diuretics (increased risk of hyperkalaemia)
 Lithium

Question 20

therapeutic drug monitoring ARB

Answer 20

Renal function should be checked at baseline via U+E – this should be repeated 1-2 weeks
after starting treatment and annually thereafter.

Older patients and patients with heart failure
should also be closely monitored clinically.

Question 21

what are the only scenarios where ARB is preffered over ACEi

Answer 21

• ACEi has caused persistent dry cough
• type 2 diabetic nephropathy
• afro-caribbean ethnicity eg second line HTN

Question 22

name 4 dihydropyridine calcium channel blockers

Answer 22

amlodipine
nifedipine
felodipine
lercanidipine

Question 23

MoA dihydropyridine calcium channel blockers

Answer 23

Target: L-type calcium channels - Dihydropyridines favour depolarised closed Ca++ channels most
commonly found in vascular smooth muscle cells

Action: Antagonist

Effect: Inhibit influx of calcium ions into vascular smooth muscle cells through L-type calcium
channels

Overall effect: Decreased arterial smooth muscle contratility leading to vasodilatation

Question 24

MoA non-dihydropyridine calcium channel blockers

Answer 24

Target: L-type calcium channels - Diltiazem and Verapamil favour the hyperpolarised Ca++ channels
more commonly found in cardiac muscle cells

Action: Antagonist

Effect: Inhibit influx of calcium ions into cardiomyocytes through L-type calcium channels

Overall effect: Negative inotropic effect – decreases cardiac contractility

Question 25

common adverse effects CCBs

Answer 25

Constipation on toilet
Flushed straining doing a poo
Straining causes a headache
Ankles swell up coz sat down for so long
Dizzy when you stand up

Question 26

important adverse effects of CCBs

Answer 26

dihydropyridine = Heart failure in patients with poor left ventricular function

non-diydropyridine = Sino-atrial and AV block with diltiazem, particularly in those taking digoxin and/or beta
blockers

Question 27

interactions CCBs dihydropyridine

Answer 27

 Other antihypertensives (increased hypotensive effect)

 Simvastatin – increased risk of myopathy therefore dose of statin should be reduced

 Antiepileptics (reduced efficacy of dihydropyridines)

 Digoxin (increased plasma digoxin concentration)

 Theophylline (increased plasma theophylline concentration)

Question 28

interactions CCBs non-dihydropyridine

Answer 28

 Antihypertensives (increased hypotensive effect)

 Beta blockers (asystole, severe hypotension, heart failure)

 Anti-arrhythmics (increased risk of bradycardia, AV block and myocardial depression)