Aldosterone antagonists _ Les Diuretiques

Question 1

Mechanism of action ?

Answer 1

Aldosterone is a mineralocorticoid secreted by the adrenal cortex, it exerces its effect on the distal tubules increasing the activity of ENaC that promotes the reabsorption of Na &water while excreting K
Aldosterone antagonists bind competitively to Aldosterone receptors, their effect is greatest in cases of HyperAldosteronism or increased levels of Aldosterone. (Cirrhosis)

Question 2

Indications ?

Answer 2

• Ascites &oedema due to cirrhosis
• Chronic heart failure, of at least moderate severity or rising within a month of myocardial infarction associated to b-blocker and ACE/angiotensin inhibitor.
• Primary hyperaldosteronism.

Question 3

Important AE ?

Answer 3

• Hyperkaliemia inducing a range of consequences; muscle cramps/weakness, arrhythmias, cardiac arrest.
• Gynecomastia, in both genders, swallowing &tenderness of the tissue under nipples &impotence. This is begnin &reversible. Reassure men, particularly.
• Liver impairment &jaundice.
• Stevens Johnson’s syndrome which is a T-cell hypersensitivity syndrome responsible for bullous skin eruption.

Question 4

Important cautions ?

Answer 4

Contraindicated in liver impairment, hyperkaliemia, Addison’s disease. Should be avoided in pregnancy &lactating women.

Question 5

Addison’s disease ?

Answer 5

Primary adrenal insufficiency/Hypoadrenalinism in which adrenal glands produce low to no adrenaline &aldosterone.

Question 6

Important interactions ?

Answer 6

Preferably not to combine with other hyperkaliemic drugs, ACE/angiotensin inhibitors (association can prove efficient in some cases with appropriate monitoring).

Question 7

Flip for a clinical tip

Answer 7

Spironolactone is a weak diuretic &takes several days for its effect to manifest. This is why, it also comes in combined preparations with thiazide/loop diuretic; serving both the counteract of potassium increased levels &potentializing diuretic effect.

Question 8

Name some Aldosterone antagonists Generics ?

Answer 8

ALDACTONE 25, 50, 75mg Cp secables.
(Canreonate de K) SOLUDACTONE lyoph pr lyoph usage parenteral.
SPIROCTAN 50,75 mg gel.
INSPRA (Epleronone) 25, 50mg Cp pellic.

Question 9

Aldosterone antagonists come in what forms ?

Answer 9

Oral preparations only. Aldosterone is approved for all indications, while Epleronone is exclusively licensed for heart failure.
Generally prescribed in a regular once daily uptake with food. Ex, 100 mg for ascites, 25mg for heart failure.