Aldosterone Blocker: What It Is, How It Works, and What You Need to Know

When your body makes too much aldosterone, a hormone that tells your kidneys to hold onto salt and water. Also known as a mineralocorticoid, it can raise your blood pressure, strain your heart, and cause swelling. An aldosterone blocker, a type of medication that stops aldosterone from doing its job. These drugs are often called mineralocorticoid receptor antagonists because they block the receptors aldosterone normally binds to.

Aldosterone blockers don’t just lower blood pressure—they help your heart and kidneys work better. People with heart failure, especially those who’ve had a heart attack, often take them to reduce fluid buildup and lower the risk of hospitalization. If you have primary hyperaldosteronism—a condition where your adrenal glands overproduce aldosterone—these drugs can be a key part of treatment. They’re also used when other blood pressure meds aren’t enough, or when someone can’t tolerate ACE inhibitors or ARBs. Unlike diuretics that flush out water randomly, aldosterone blockers target the root cause: too much of this specific hormone.

These medications work slowly but steadily. You won’t feel a sudden change, but over weeks, swelling goes down, blood pressure drops, and breathing gets easier. Common ones include spironolactone and eplerenone. Spironolactone has been around for decades and is cheap, but it can cause side effects like breast tenderness in men. Eplerenone is newer, more selective, and often has fewer hormonal side effects. Both can raise potassium levels, so your doctor will check your blood regularly. You can’t take them if you have severe kidney disease or already have high potassium. They’re not for everyone, but for the right person, they make a real difference.

What you’ll find below are real guides from people who’ve dealt with these drugs—whether they’re managing heart failure, dealing with resistant high blood pressure, or looking at alternatives to traditional diuretics. You’ll see how aldosterone blockers fit into broader treatment plans, what side effects to watch for, and how they compare with other medications like beta-blockers or ACE inhibitors. These aren’t theory pieces—they’re practical, lived experiences from users and clinicians who’ve been there.