Hyperaldosteronism Flashcards
1
Q
Aldosterone antagonist (Spironolactone, epleronone)
Common indications
A
- Ascites and oedema due to liver cirrhosis- spironolactone is the first-line diuretics
- Chronic HF- of at least moderate severity or arising within 1 month of a MI, usually as an addition to BB and ACEI/ARB
- Primary Hyperaldosteronism- For patients awaiting surgery or for whom surgery is not an option
2
Q
Aldosterone antagonist (Spironolactone, epleronone)
MOA
A
- Aldosterone is a mineralocorticoid that is produced in the adrenal cortex
- It acts on mineralocorticoid receptors in the distal tubules of the kidney to increase the activity of luminal epithelial sodium channels (ENaC)
- This increases the reabsorption of sodium and water (Which elevates blood pressure) with the by-product of increased potassium excretion
- Aldosterone antagonists inhibit the effect of aldosterone by competitively binding to the aldosterone receptor.
- This increases sodium and water excretion and potassium retention their effect is greatest in primary hyperaldosteronism or when circulating aldosterone is increased e.g. in cirrhosis
3
Q
Aldosterone antagonist (Spironolactone, epleronone)
Important adverse effects
A
- An important adverse effect of aldosterone antagonist is hyperkalaemia, which can lead to muscle weakness, arrhythmias and even cardiac arrest
- Spironolactone causes gynecomastia, which can have a significant impact on patient adherence
- Aldosterone antagonists can cause liver impairment and jaundice and are a cause of steves-johnson syndrome (T-cell. mediated hypersensitivity reaction) that causes a bullous skin eruption
4
Q
Aldosterone antagonist (Spironolactone, epleronone)
Warnings
A
- Aldosterone antagonists are contraindicated in patients with severe renal impairment, hyperkalaemia and Addison’s disease (Who are aldosterone deficient)
- Aldosterone antagonists can cross the placenta during pregnancy and appear in breast milk so should be avoided where possible in pregnancy or lactating women
5
Q
Aldosterone antagonist (Spironolactone, epleronone)
Important interactions
A
- The combination of aldosterone antagonist with other potassium-elevating drugs, including ACEI and ARB, increases the risk of hyperkalaemia
- Nevertheless, when supported by appropriate monitoring, this may be a beneficial combination in the context of heart failure
- Aldosterone antagonists should not be combined with potassium supplements except in specialist practice
6
Q
Aldosterone antagonist (Spironolactone, epleronone)
Administration and communication
A
- Spironolactone should generally be taken with food
- When starting treatment with spironolactone, particularly in high doses, it is particularly important to warn men about the possibility of growth and tenderness of tissue under the nipples and impotence
- Reassure them that such effects are benign and reversible, but acknowledge that they may be uncomfortable and embarrassing
- Ask patients to return if they have troublesome side effects, as these may respond to dose reduction
- Advise all patients that aldosterone antagonists can cause their potassium levels to rise and reinforce the importance of attending for blood tests
7
Q
Aldosterone antagonist (Spironolactone, epleronone)
Monitoring
A
- Efficacy should be monitored by patient report of symptoms and clinical findings, e.g. reduction in ascites, oedema and/or blood pressure
- Safety should be monitored by checking renal function and serum potassium concentration due to risk of renal impairment and hyperkalaemia
