Thiazide diuretics (Bendroflumethiazide)

Question 1

What are the indications of bendroflumethiazide?

Answer 1

1) thiazides are alternative treatment for hypertension , where Ca2+ channel blockers are unsuitable.
2) An additional hypertension treatment. (add on to calcium channel blocker + ace inhibitor/angiotensin receptor blocker)

Question 2

How does bendroflumethiazide work?

Answer 2

1) Act on the distal convoluted tubules to stop the Na+/2Cl- co-transporter . So electrolytes + water remains in the lumen and are excreted in urine.
2) Vasodilation

Question 3

What are the adverse effects of bendroflumethiazide?

Answer 3

1) hyponatraemia
2) hypokalaemia –> cardiac arrhythmias
3) impotence

Question 4

What conditions should bendroflumethiazide be avoided in?

Answer 4

HypoNa+
HypoK+
Gout (reduced uric acid excretion)

Question 5

what are the important interactions of bendroflumethiazide?

Answer 5

1) NSAIDs reduce the effectiveness of thiazides

2) avoid use with other K+ lowering drugs e.g. loop diuretics.

Question 6

how are thiazides prescribed / taken?

Answer 6

Usually taken orally daily. In morning.

Bendroflumethiazide - 2.5mg daily

Question 7

How is the efficacy of thiazides monitored?

Answer 7

1) Blood pressure should decrease

2) less oedema

Question 8

Why is the combination of an ACE inhibitor / ARB with a thiazide useful?

Answer 8

Both help to lower BP.
However ACEi / ARB cause hyperkalaemia.
Thiazides cause Hypokalaemia.
Used together can help maintain neutral potassium balance.