Diuretics: A cause of low potassium?

I have high blood pressure and take several medications for it, including a diuretic and an ACE inhibitor. My doctor says my potassium level is too low. Could this be caused by my medications?

- Jan / Nebraska

Answer

Many diuretics decrease potassium in the blood. Diuretics lower blood pressure by helping your body eliminate sodium and water, which reduces blood volume and decreases pressure on your artery walls. When your body excretes excessive amounts of water, it also loses potassium. This can lead to low potassium levels in your blood (hypokalemia).

There are potassium-sparing diuretics that don't cause this problem. These include:

• Spironolactone (Aldactone)
• Eplerenone (Inspra)
• Triamterene (Dyrenium)
• Amiloride (Midamor)

Angiotensin-converting enzyme (ACE) inhibitors reduce blood pressure by helping to relax blood vessels. ACE inhibitors usually increase potassium levels in your blood.

If you're taking an ACE inhibitor and getting enough potassium in your diet but your potassium level is still low, your doctor may recommend further testing to help identify the underlying cause. Rarely, low potassium may be due to overproduction of the hormone aldosterone (hyperaldosteronism), which increases potassium loss by the kidneys.

Treatment of low potassium may include:

• Increasing potassium in your diet
• Use of potassium supplements
• Changing to a potassium-sparing diuretic

MORE ON THIS TOPIC

• Diuretics
• High blood pressure (hypertension)
• Low potassium (hypokalemia): What causes it?

RELATED

• Beta blockers: How do they affect exercise?
• Beta blockers: Do they cause weight gain?
• High blood pressure and sex: Overcome the challenges