Drugs used in the treatment of hypertension

Question 1

Which one of the following suffixes indicate that the drug is an ACE inhibitor?
a) -olol
b) -pril
c) -artan
d) -zosin

Answer 1

B

Question 2

Which one of the following beta-blockers is cardio-selective?
a) Atenolol
b) Propranolol
c) Carvedilol
d) Labetalol

Answer 2

A

Question 3

Match the drug with the appropriate statement
Drug Atenolol
Enalapril
Doxazosin

Statement
Dry cough and angioedema
Indicated for benign prostatic hyperplasia Caution advised in people with asthma and COPD

Answer 3

Sure, let’s match the drugs to the appropriate statements:

1. Atenolol: Caution advised in people with asthma and COPD
2. Enalapril: Dry cough and angioedema
3. Doxazosin: Indicated for benign prostatic hyperplasia

Question 4

Which one of the following drugs are more likely to be used as first-line treatment of hypertension according to EML/STG’s?
a) Atenolol
b) Doxazosin
c) Enalapril
d) Hydrochlorothiazide

Answer 4

c

Question 5

Major risk factors for hypertension

Answer 5

Major risk factors for hypertension
* Levels of systolic and diastolic Bp
Smoking
* Dyslipidaemia:
* Total cholesterol > 5.1 mmol/l, OR
* LDL > 3 mmol/l, OR
* HDL men < 1 and women < 1.2 mmol/l
* Diabetes mellitus
* Men > 55 years
* Women > 65 years
* Family history of early onset of CVD:
* Men aged < 55 years
* Women aged < 65 years
* Waist circumference: abdominal obesity:
* Men ≥ 102 cm
* Women ≥ 88 cm
* The exceptions are South Asians and Chinese: men: > 90 cm and women: > 80 cm

Question 6

Target organ damage (TOD)

Answer 6

Target organ damage (TOD):
* Left ventricular hypertrophy
* Hypertensive retinopathy
* Microalbuminuria or positive urine dipsticks for albuminuria or elevated albumin
creatinine ratio
* Elevated creatinine level (or eGFR <60ml/min)

Question 7

Associated clinical conditions:

Answer 7

Ischaemic heart disease / MI
* Heart failure
* Stroke / transient ischemic attack(TIA)
* Chronic kidney disease
* Peripheral arterial disease

Question 8

Sites of action of
the following drugs are shown

Answer 8

1, vasodilators; 2,
β -adrenoceptor antagonists ( β -
blockers);
3, α-adrenoceptor antagonists (α-blockers);
4, angiotensin receptor
antagonists;
5, centrally acting sympatholytics;
6, angiotensin-converting enzyme (ACE)
inhibitors;
7, direct renin inhibitors; and
8, diuretics. The vasodilators, sympatholytic
drugs, and angiotensin inhibitors reduce PVR; β -adrenoceptor blockers primarily reduce
cardiac output; and diuretics promote sodium excretion and reduce blood volume.

Question 9

Antihypertensives

Answer 9

vasodilators: calcuim blockers and agents acting on arterial smooth muscle

diuretics
centrally acting agents

Question 10

Agents acting on arteriolar smooth muscle

Answer 10

Hydralazine

Minoxidil

Question 11

Hydralazine

Answer 11

Uncertain mechanism of action: relax arteries and arterioles = vasodilation =
↓peripheral resistance = ↓ BP accompanied by reflex tachycardia and ↑
CO (interferes with action of inositol triphosphate on Ca+ release from
the sarcoplasmic reticulum)
Indications: 4
th line treatment for hypertension (low doses in combination
with b-blocker), supplementary tx in chronic cardiac failure
Adverse effect: long-term use can cause immune disorder resembling SLE
Indicated for HF in patients of African origin in combination with long-acting
nitrate

Question 12

Minoxidil

Answer 12

Direct acting vasodilator(by activating K+ channels), increases CO and
accompanied by tachycardia
Potent and long-acting vasodilator
Last line unresponsive/refractory hypertension (NOT used as
monotherapy, concurrent diuretic and b-blocker often required)
Adverse effect: marked salt and water retention (NOT for heart failure),
prescribed with a loop diuretic, hirsutism

Question 13

• What are the 2 categories of calcium-channel blockers and examples?

Answer 13

elective CCB with mainly
vascular effects

Selective CCB with direct
cardiac effects

Question 14

Loop diuretics: indications

Answer 14

• Oedema, pulmonary oedema
• Oedema secondary to heart failure, liver cirrhosis, etc.
• Reserved for use in hypertension for patient with poor renal function
  (CrCL<30ml/min)
• Despite greater natriuretic effect than thiazides, usually less effective
  that thiazides to control blood pressure in patients with normal renal

function
* Hypercalcaemia

Question 15

Loop diuretics: pharmacokinetics

Answer 15

• Route of administration: oral or IV
• Partly metabolised before excreted in the urine

Question 16

Loop diuretics: adverse effects

Answer 16

Hypokalaemia, hypomagnesaemia, hypocalcaemia, hyponatraemia, * Hyperuricaemia (gout), hypochloraemic alkalosis
* Dehydration, hypotension, hypovolaemia
* Endocrine abnormalities like thiazides
* Hearing loss
* Hypersensitivity (sulphonamide structure)

Question 17

Potassium-sparing diuretics: mechanism of action.

Answer 17

Sodium enters the principal cells through sodium channels. Sodium is then
transferred into the interstitial fluid by the sodium pump, while potassium is pumped in the opposite direction and then moves through potassium channels into the tubular fluid.

Question 18

Aldosterone

Answer 18

Aldosterone stimulates these processes by increasing the synthesis of messenger RNA that encodes for sodium channel and
sodium pump proteins.

Question 19

The potassium-sparing diuretics exert

Answer 19

The potassium-sparing diuretics exert
their effects via two mechanisms:
amiloride and triamterene inhibit the
entrance of sodium into the principal cells, whereas spironolactone blocks the mineralocorticoid (aldosterone) receptor and thereby inhibits sodium reabsorption and potassium secretion.

Question 20

Where in the nephron does Spironolactone exert its effects?

a. Proximal convoluted tubule
b. Loop of Henle
c. Distal convoluted tubule and collecting duct
d. Bowman’s capsule

Answer 20

Spironolactone acts on the distal tubule and collecting duct by blocking aldosterone receptors.

Question 21

What is the result of aldosterone receptor blockade by Spironolactone in the kidneys?

a. Increased potassium excretion
b. Increased sodium reabsorption
c. Decreased sodium reabsorption and decreased potassium excretion
d. Decreased urine output

Answer 21

By blocking aldosterone receptors, Spironolactone promotes sodium excretion and reduces renal potassium excretion.

Question 22

How does Spironolactone affect sodium channels and the sodium pump in the kidney?

a. Enhances their activity
b. Inhibits their expression
c. Increases their synthesis
d. No effect on these proteins

Answer 22

pironolactone blocks the mineralocorticoid receptor, which interacts with DNA to promote the expression of genes for sodium channels and the sodium pump, leading to reduced sodium reabsorption

Question 23

Which condition is Spironolactone primarily used to treat due to its mechanism of action?

a. Hypokalemia
b. Hyperkalemia
c. Hypertension
d. Hypotension

Answer 23

Hypertension
Rationale: Spironolactone is used to treat hypertension and conditions like heart failure by reducing sodium reabsorption and thereby lowering blood pressure.

Question 24

In addition to its role in the kidney, what other effect does Spironolactone have due to its aldosterone antagonism?

a. Decreased blood glucose levels
b. Reduced cardiac fibrosis
c. Increased urine concentration
d. Enhanced muscle contraction

Answer 24

b. Reduced cardiac fibrosis
Rationale: By antagonizing aldosterone, Spironolactone can reduce cardiac fibrosis, which is beneficial in conditions like heart failure.

Question 25

Spironolactone: indications

Answer 25

• Prevent hypokaleamia
• Primary hyperaldosteronism
• Reduce mortality in people with heart failure
• Antiandrogenic effects: polycystic ovary disease and hirsutism in
  women

Question 26

. Which of the following is a known adverse effect of Spironolactone?

a. Hypokalemia
b. Gynecomastia
c. Hypertension
d. Hypernatremia

Answer 26

Gynecomastia
Rationale: One of the antiandrogenic effects of Spironolactone is gynecomastia, which is breast enlargement in men.

Question 27

What electrolyte imbalance is a common adverse effect of Spironolactone?

a. Hyperkalemia
b. Hypocalcemia
c. Hypernatremia
d. Hypokalemia

Answer 27

Hyperkalemia
Rationale: Spironolactone can lead to hyperkalemia due to its mechanism of decreasing renal potassium excretion.

Question 28

Spironolactone is contraindicated in patients with which of the following conditions?

a. Liver impairment
b. Heart failure
c. Kidney impairment (eGFR <30 ml/min) and pregnancy
d. Hypertension

Answer 28

Kidney impairment (eGFR <30 ml/min) and pregnancy
Rationale: Spironolactone is contraindicated in patients with significant kidney impairment due to the risk of hyperkalemia and other complications

Question 29

What are the antiandrogenic effects associated with Spironolactone?

a. Hypertension and tachycardia
b. Gynecomastia and impotence
c. Weight loss and hyperactivity
d. Hypernatremia and dehydration

Answer 29

Gynecomastia and impotence
Rationale: Spironolactone can cause antiandrogenic effects such as gynecomastia and impotence in men.

Question 30

Why should Spironolactone be used with caution or avoided in patients with kidney impairment?

a. It causes hypokalemia
b. It can lead to nephrotoxicity
c. It increases the risk of hyperkalemia
d. It is metabolized by the kidney

Answer 30

It increases the risk of hyperkalemia
Rationale: Spironolactone should be avoided or used with caution in patients with kidney impairment because it can exacerbate hyperkalemia.

Question 31

Which of the following is NOT a contraindication for the use of Spironolactone?

a. Severe kidney impairment
b. Hypertension
c. Hyperkalemia
d. Addison’s disease

Answer 31

b. Hypertension
Rationale: Hypertension is actually an indication for the use of Spironolactone, not a contraindication.

Question 32

Centrally acting antiadrenergic drugs

Answer 32

Reserpine,
* Methyldopa*,
* Moxonidine

Question 33

What is the primary mechanism of action of methyldopa?

a. Inhibits the reuptake of noradrenaline
b. Blocks aldosterone receptors
c. Acts as a false transmitter precursor for noradrenaline synthesis
d. Directly stimulates α1 receptors

Answer 33

Acts as a false transmitter precursor for noradrenaline synthesis
Rationale: Methyldopa is taken up by noradrenergic neurons, where it is converted to α-methylnoradrenaline, a false transmitter that interferes with noradrenaline synthesis and release.

Question 34

How does α-methylnoradrenaline affect presynaptic α2 receptors, and what is the result?

a. It blocks α2 receptors, increasing noradrenaline release.
b. It stimulates α2 receptors, reducing noradrenaline release.
c. It has no effect on α2 receptors.
d. It blocks β1 receptors, reducing heart rate

Answer 34

. It stimulates α2 receptors, reducing noradrenaline release.
Rationale: α-Methylnoradrenaline is more active on presynaptic α2 receptors, enhancing the autoinhibitory feedback mechanism, which reduces the release of noradrenaline and contributes to its hypotensive effect.

Question 35

Why is methyldopa particularly used for managing hypertension in pregnancy?

a. It has no teratogenic effects and is safe for the unborn baby.
b. It is the most potent antihypertensive available.
c. It primarily acts on the kidneys, which is beneficial during pregnancy.
d. It has fewer side effects compared to other antihypertensives.

Answer 35

s no teratogenic effects and is safe for the unborn baby.
Rationale: Methyldopa is commonly used in the second half of pregnancy because there is considerable experience with its use and no suggestion of harm to the unborn baby.

Question 36

What are some common side effects associated with methyldopa use?

a. Hypertension and tachycardia
b. Sedation and liver toxicity
c. Increased appetite and weight gain
d. Insomnia and anxiety

Answer 36

Sedation and liver toxicity
Rationale: Methyldopa produces side effects typical of centrally acting antiadrenergic drugs, such as sedation, and carries risks of immune haemolytic reactions and liver toxicity.

Question 37

How does methyldopa’s mechanism of action result in a reduction of vasoconstriction?

a. It increases the activity of noradrenaline on α1 receptors.
b. It decreases the activity of α-methylnoradrenaline on α1 receptors.
c. It enhances the release of noradrenaline from synaptic vesicles.
d. It blocks the activity of noradrenaline on β1 receptors.

Answer 37

b. It decreases the activity of α-methylnoradrenaline on α1 receptors.
Rationale: α-Methylnoradrenaline is less active than noradrenaline on α1 receptors, making it less effective in causing vasoconstriction, which contributes to its hypotensive action.

• Absorbed slowly by mouth
• Excreted unchanged or as conjugate
• Plasma half-life 6 hours

Question 38

Methydopa Adverse effects

Answer 38

: hypotension, drowsiness, diarrhoea, impotence,
hypersensitivity reactions

Question 39

A 45-year-old female patient with a history of hypertension is being managed with antihypertensive therapy. She is currently on hydrochlorothiazide (HCTZ) and her blood pressure is not adequately controlled. The clinician is considering a stepwise approach to manage her hypertension.

Answer 39

Initial Step:
Start with Hydrochlorothiazide (HCTZ)

Step 1: Add First Agent
Option A: Enalapril
Option B: Amlodipine

Step 2: Increase Dose of Second Agent

Step 3: Add Third Agent
Option A: Enalapril
Option B: Amlodipine

Step 4: Increase Dose of Third Agent

Step 5: Increase Dose of HCTZ and Add Spironolactone

Question 40

A 45-year-old hypertensive patient is currently on hydrochlorothiazide (HCTZ). Her blood pressure is still not controlled. Which of the following is the next best step?

a. Increase the dose of HCTZ
b. Add Enalapril
c. Add Amlodipine
d. Both b and c are correct options

Answer 40

Both b and c are correct options
Rationale: When HCTZ alone is not sufficient, the next step is to add another antihypertensive agent such as Enalapril (an ACE inhibitor) or Amlodipine (a calcium channel blocker).

Question 41

After adding Enalapril to the treatment regimen of the patient on HCTZ, her blood pressure remains uncontrolled. What is the next step in her management?

a. Add Amlodipine
b. Increase the dose of Enalapril
c. Increase the dose of HCTZ
d. Add Spironolactone

Answer 41

Increase the dose of Enalapril
Rationale: If the addition of Enalapril does not control blood pressure, the next logical step is to increase the dose of the second agent before adding a third agent.

Question 42

Doxazosin in hypertension.

Answer 42

Consider 4th / 5th line for use in hypertension, if BPH is a co-morbidity