Hypertension - Medications

Question 1

Indications of ACE Inhibitors.

Answer 1

1. Hypertension.
2. Chronic Heart Failure.
3. Ischaemic Heart Disease.
4. Diabetic Neprhopathy or CKD with Proteinuuria.

Question 2

Mechanism of Action of ACE Inhibitors (3).

Answer 2

1. Block ACE (Angiotensin-Converting Enzyme) which prevents conversion of Angiotensin I into Angiotensin II.
2. Angiotensin II is a vasoconstrictor and stimulates aldosterone secretion.
3. Reduction of Peripheral Vascular Resistance (Afterload) and Dilation of Efferent Glomerular Arteriole and Promote Water + Salt Excretion (Preload).

Question 3

Adverse Effects of ACE Inhibitors (5).

Answer 3

1. Hypotension.
2. Persistent Dry Cough (Increased levels of Bradykinin - usually inactivated by ACE).
3. Hyperkalaemia (Low Aldosterone levels).
4. Renal Failure (if Renal Artery Stenosis - efferent glomerular arteriole is constricted.
5. Rare : Angioedema and Anaphylactoid Reactions.

Question 4

Contraindications of ACE Inhibitors & ARBs. (3).

Answer 4

1. Renal Artery Stenosis.
2. Acute Kidney Injury.
3. Pregnancy & Breastfeeding.

Question 5

Cautions of ACE Inhibitors & ARBs (3).

Answer 5

1. Potassium Elevating Drugs (Risk of Hyperkalaemia).

2. Chronic Kidney Disease.

Question 6

Indications of ARBs.

Answer 6

Same as ACE Inhibitors - when ACE Inhibitors are not tolerated.

Question 7

Mechanism of Action of ARBs.

Answer 7

Block action of Angiotensin II on AT1 receptor.

Question 8

Adverse Effects of ARBs (3).

Answer 8

1. Hypotension.
2. Renal Failure.
3. Hyperkalaemia.

Question 9

Indications of CCBs (3).

Answer 9

1. Hypertension.
2. Stable Angina.
3. Supraventricular Arrhythmias - Dilitiazem and Verapamil.

Question 10

Mechanism of Action of CCBs (3).

Answer 10

1. Reduce Ca2+ entry into vascular and cardiac cells.
2. Relaxation and vasodilation in arterial smooth muscle - lower arterial pressure.
3. Reduce myocardial contractility and suppress cardiac conduction across AV note.

Question 11

Types of CCBs (2).

Answer 11

1. DHPs e.g. Amlodipine and Nifedipine - vascular selective.

2. Non-DHP e.g. Verapamil (most cardioselective) and Dilitiazem.

Question 12

Adverse Effects of CCBs (2).

Answer 12

1. DHP - Ankle Swelling, Flushing, Headache and Palpitations (Vasodilation and Compensatory Tachycardia).
2. Verapamil - Constipation, Bradycardia, Heart Block (if given with B-Blocker) and Cardiac Failure.

Question 13

Contraindications of CCBs (2).

Answer 13

1. DHP - Unstable Angina and Severe Aortic Stenosis.

2. Non-DHP - Poor Left Ventricular Function and AV Node Conduction Delay and B-Blocker Use.

Question 14

Examples of Thiazide and Thiazide-Like Diuretics (3).

Answer 14

Thiazide : Bendroflumethiazide.

Thiazide-Like : Indapamide, Chlortalidone.

Question 15

Indications of Thiazide Diuretics.

Answer 15

Hypertension.

Question 16

Mechanism of Action of Thiazide Diuretics.

Answer 16

Inhibit Na+/Cl- cotransporter in DCT which prevents resorption of Sodium and water so drop in ECF volume.

Question 17

Adverse Effects of Thiazide Diuretics (4).

Answer 17

1. Hypokalaemia - Cardiac Arrhythmias, Hypernatraemia, Hypercalcaemia.
2. Impotence in Men.
3. Impaired Glucose Tolerance.
4. Gout.

Question 18

Monitoring of ACE Inhibitors.

Answer 18

1. Check U&Es before and after increasing dose - increase in serum creatinine by 30% from baseline and in Potassium up to 5.5 mmol/L.