People have been warned that salt (sodium chloride) is dangerous, especially for people with high blood pressure. New research suggests that is only true when people with hypertension consume a lot of sodium (more than 6 grams daily). Potassium chloride is frequently recommended as a salt substitute but it can pose unexpected dangers for some people. This reader asks a common question:
Q. I recently was diagnosed with high blood pressure and advised to eliminate salt. My question to you: is salt substitute (potassium chloride) safe?
A. Ask your physician to review a study that was recently published in The Lancet (online, May 20, 2016). This research showed that a really low-salt diet may be counterproductive and increase the risk of cardiovascular complications (heart attacks, strokes, heart failure deaths). They also found that too much salt (over 6,000 mg daily) is also dangerous for people with hypertension.
Listen to the Lead Author Explain the Confusing Sodium Story:
We know this seems counterintuitive and you may not wish to wade through a lot of medical terminology. That’s why we interviewed the lead author, Andrew Mente, PhD, Associate Professor in the Department of Clinical Epidemiology & Biostatistics at McMaster University on our radio show last Saturday. You can listen to his 10-minute explanation of the results of this landmark study at this link.
The Topsy-Turvy World of Diuretics:
Please pay attention, this is really confusing!
Too Little Potassium (Hypokalemia)
Most diuretics deplete the body of potassium. Such drugs are swallowed by tens of millions of Americans every day. We are referring to drugs like:
Chlorothiazide (Diuril, Diachlor, Diurigen)
Ethacrynic acid (Edecrin)
Hydrochlorothiazide (Esidrix, HydroDIURIL, Oretic)
Methyclothiazide (Aquatensen, Enduron)
Trichlormethiazide (Diurese, Metahydrin, Naqua)
Such diuretics are also included in the formulas of many combination blood pressure pills. They flush potassium out of the body and often lead to something called hypokalemia.
When serum potassium drops below 3.5 mEq/L it can cause irregular pulse, muscle cramps, breathing difficulties and weakness.
Too Much Potassium (Hyperkalemia)
We promised confusion, so here goes. Although most diuretics deplete the body of potassium, there are some that actually help the body retain potassium. They include:
Potassium Sparing Diuretics:
- Eplerenone (Inspra)
- Spironolactone (Aldactone, Aldactazide)
- Triamterene (Dyrenium, Dyazide, Maxzide)
- Amiloride (Midamor, Moduretic)
When potassium-sparing diuretics are added to certain blood pressure medications, they can lead to a buildup of potassium. The same thing can occur when a salt substitute containing potassium chloride is added to such medications for hypertension.
These include ACE Inhibitors and ARBS:
• Benazepril (Lotensin)
• Captopril (Capoten)
• Enalapril (Vasotec)
• Lisinopril (Prinivil, Zestril)
• Quinapril (Accupril)
• Ramipril (Altace)
ARBs (Angiotensin Receptor Blockers)
• Candesartan (Atacand)
• Irbesartan (Avapro)
• Losartan (Cozaar)
• Olmesartan (Benicar)
• Telmisartan (Micardis)
• Valsartan (Diovan)
The Dangers of Too Much Potassium (Hyperkalemia)
When potassium levels exceed 5 mEq/L the risk is hyperkalemia. This can be equally dangerous as too little potassium. Here are symptoms to be alert for:
Palpitations, heart rhythm changes
Tingling or numbness in lips, feet, or hands
The People’s Pharmacy Bottom Line on Potassium Chloride:
Salt substitutes containing potassium chloride are a reasonable option as long as you are not taking certain blood pressure pills that preserve potassium. Always check with your pharmacist and physician to make sure you do not end up with a drug interaction that could cause life-threatening irregular heart beats!
Here is a link to an article of similar interest: “A Deadly Interaction Often Ignored by Doctors and Pharmacists”
You can learn more about these complicated issues in our Guide to Blood Pressure Treatment.