Salt Substitutes and ACE Inhibitors or ARBs: Hidden Potassium Risks

Many people switch to salt substitutes thinking they’re making a healthier choice-especially if they’re managing high blood pressure. But for those taking ACE inhibitors or ARBs, this simple swap can be dangerous. These substitutes often replace sodium chloride with potassium chloride, and when combined with blood pressure medications that already affect potassium levels, the result can be life-threatening.

What’s in Salt Substitutes?

Most salt substitutes aren’t just "less salt." They’re a different chemical entirely. Products like LoSalt, NoSalt, or Heart Salt contain anywhere from 50% to 100% potassium chloride instead of sodium chloride. A typical ¼ teaspoon of regular salt gives you about 1,500 mg of sodium. The same amount of a 50/50 potassium-sodium substitute delivers around 400-600 mg of potassium. That might not sound like much, but for someone with kidney problems or on certain medications, it adds up fast.

Regular table salt is about 40% sodium by weight. Potassium chloride is about 52% potassium. When you swap half your salt for a substitute, you’re cutting sodium by 300-400 mg daily but adding 500-600 mg of potassium. For most people, that’s fine. For others, it’s a ticking time bomb.

How ACE Inhibitors and ARBs Interfere with Potassium

ACE inhibitors (like lisinopril, enalapril) and ARBs (like losartan, valsartan) work by blocking a hormone system called the renin-angiotensin-aldosterone system. That’s good for lowering blood pressure-but it also reduces aldosterone, a hormone that tells your kidneys to flush out potassium. Less aldosterone means potassium builds up in your blood.

That’s why doctors regularly check potassium levels in patients on these drugs. But many don’t ask about salt substitutes. A 2022 Mayo Clinic study found that 63% of hyperkalemia cases in people on these medications came from dietary sources, not supplements or kidney failure alone. That’s alarming. People think they’re eating clean, low-sodium food-and they’re not realizing that their "healthy" salt substitute is pushing their potassium into the danger zone.

Who’s at Highest Risk?

Not everyone is at risk. But if you fall into any of these groups, you need to be extremely careful:

• You have chronic kidney disease (CKD), especially stage 3 or worse (eGFR below 60)
• You have diabetes and reduced kidney function (up to 20% of diabetics with CKD have hyporeninemic hypoaldosteronism, which makes potassium retention worse)
• You’re over 65
• You’re taking other drugs that raise potassium, like spironolactone or NSAIDs

According to CDC data from 2022, 15% of U.S. adults have CKD. The American College of Cardiology says 40% of hypertension patients are on ACE inhibitors or ARBs. That means millions of people are walking around with a hidden risk they don’t even know about.

A 2004 case report in the Journal of the Royal Society of Medicine documented a 72-year-old man who went into cardiac arrest after using LoSalt while on nabumetone and with mild kidney issues. His potassium level hit 7.8 mmol/L-life-threatening above 6.5. He survived, but only because he got to the hospital in time.

The Real Numbers: When Danger Becomes Real

Serum potassium levels above 5.0 mmol/L are considered high. Above 6.0 mmol/L, you’re at serious risk for irregular heart rhythms. Above 6.5, cardiac arrest can happen without warning.

For the general population, potassium-enriched salt substitutes are safe-and even beneficial. A 2025 JAMA study tracking 21,000 people found a 14% drop in stroke recurrence among those using low-sodium, potassium-enriched salt. But for people with eGFR below 60, the risk skyrockets. The Chronic Kidney Disease Prognosis Consortium found hyperkalemia events jumped from 0.8 per 100 person-years in healthy people to 8.7 per 100 person-years in those with CKD on ACE inhibitors or ARBs.

That’s more than a tenfold increase.

What Patients Are Saying

Real stories show this isn’t theoretical. On Reddit, a user with 4,200 karma wrote: "Woke up in the ER with potassium at 6.3 after using Heart Salt for three weeks while on lisinopril." Another user on Drugs.com, Martha from Michigan, said she felt "severe muscle weakness and irregular heartbeat" after switching to potassium salt while on losartan.

On Amazon, 7% of reviews from people who mentioned kidney conditions said their doctor told them to stop the salt substitute after bloodwork showed high potassium. Meanwhile, 28% of negative reviews complain about a "metallic aftertaste"-a common complaint with potassium chloride. But taste isn’t the issue. Safety is.

What You Can Do Instead

You don’t need potassium chloride to reduce sodium. There are safer, equally effective ways:

• Use herbs and spices: garlic powder, onion powder, paprika, cumin, black pepper, dried oregano, rosemary
• Try acid-based flavor boosters: lemon juice, lime juice, vinegar (balsamic, apple cider)
• Use no-salt seasoning blends like Mrs. Dash-these contain no potassium

These alternatives can cut sodium by 40-50%, almost as much as potassium salt substitutes-without the risk. And they don’t require blood tests every three months.

What Doctors and Regulators Are Doing

The problem isn’t just patient ignorance-it’s poor labeling. In 2023, the FDA found only 3 out of 12 major salt substitute brands warned against use with ACE inhibitors or ARBs. Canada mandated clear warning labels on all potassium-containing salt substitutes as of January 2024. The U.S. hasn’t.

The American Diabetes Association, the National Kidney Foundation, and the American Society of Hypertension all now recommend that doctors screen every patient on ACE inhibitors or ARBs for salt substitute use. Yet a 2023 JAMA Internal Medicine study found 78% of patients on these drugs had no idea dietary potassium could be dangerous.

There’s hope. The FDA announced proposed rulemaking in May 2024 to require clearer labeling on potassium-containing food additives. Final rules are expected in Q2 2026. Until then, the responsibility falls on you and your doctor.

What You Should Do Right Now

If you’re taking an ACE inhibitor or ARB, here’s what to do:

1. Check your medicine cabinet. Do you have any salt substitute? Look for "potassium chloride" on the label.
2. Ask your doctor: "Is it safe for me to use potassium-based salt substitutes?" Don’t assume it’s okay.
3. Get your potassium level checked if you’ve been using one-even if you feel fine. Hyperkalemia often has no symptoms until it’s too late.
4. Switch to herb-based seasonings. They’re cheaper, safer, and just as flavorful once you get used to them.
5. If you have CKD or diabetes, avoid potassium salt substitutes entirely unless your nephrologist says otherwise.

There’s no magic bullet for lowering blood pressure. But there are safe choices. You don’t need to risk your heart to cut the salt.

Final Thought: It’s Not About Cutting Salt-It’s About Choosing Wisely

The goal isn’t to eliminate salt entirely. It’s to reduce sodium without creating new dangers. For most people, potassium salt substitutes are a good tool. But for the 10-15% of the population with kidney issues or on certain medications, they’re a trap. The same product that helps one person’s blood pressure can nearly kill another.

Knowledge saves lives. If you’re on an ACE inhibitor or ARB, don’t guess. Ask. Test. Switch. Your heart will thank you.