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 on blood pressure medication. But for those taking ACE inhibitors or ARBs, this swap can be dangerous. It’s not just a minor concern. It can land you in the hospital-or worse.

What’s in those salt substitutes?

Most salt substitutes replace some or all of the sodium chloride with potassium chloride. Products like LoSalt, NoSalt, and Heart Salt can contain up to 66% potassium chloride. That sounds harmless until you realize your body doesn’t get rid of extra potassium the same way it handles sodium. Your kidneys filter it out, but if they’re not working well-or if your medication slows down that process-potassium builds up. Fast.

Why ACE inhibitors and ARBs are the problem

ACE inhibitors and ARBs are common drugs for high blood pressure, heart failure, and kidney protection in diabetics. They work by relaxing blood vessels and reducing fluid retention. But here’s the catch: they also reduce a hormone called aldosterone. Aldosterone tells your kidneys to push potassium out of your body. Less aldosterone? Less potassium gets flushed. Now add a salt substitute loaded with potassium, and you’ve created a perfect storm.

A 2004 case report in the Journal of the Royal Society of Medicine described a 72-year-old man who went into cardiac arrest after using LoSalt while taking nabumetone and having mild kidney issues. His potassium level hit 7.8 mmol/L. Normal is 3.5 to 5.0. Above 6.5? Risk of sudden heart rhythm problems skyrockets. He didn’t survive.

Who’s at highest risk?

You’re in danger if you have:

• Chronic kidney disease (CKD), especially stage 3 or higher (eGFR below 60)
• Diabetes with kidney involvement
• Age over 65
• Already high potassium levels (above 4.5 mmol/L)

About 15% of U.S. adults have CKD. That’s 37 million people. And 40% of those with high blood pressure are on ACE inhibitors or ARBs. That means millions are walking around with this hidden risk. A 2019 study from the Chronic Kidney Disease Prognosis Consortium found that among people with CKD on these drugs, the rate of dangerous hyperkalemia jumped to 8.7 events per 100 person-years-up from less than 1 in the general population.

What does the science say about safety?

The 2025 JAMA Network study of 21,000 people showed that using a salt substitute with 25% potassium chloride lowered stroke risk by 14%. That’s huge. But here’s the fine print: those participants had normal kidney function. The study didn’t include people with CKD or those on ACE inhibitors or ARBs.

Dr. Sarah Anderer, lead author of that study, says potassium substitutes are safe for most people. But Dr. Mark S. Segal, a nephrologist, warns: “Don’t apply those results to patients with advanced kidney disease.” They’re not contradicting each other-they’re talking about different groups.

The American Diabetes Association is even clearer: people with diabetes and kidney problems face a “disproportionately high” risk of hyperkalemia when combining salt substitutes with these medications.

Real people, real consequences

Reddit threads and drug review sites are full of stories that don’t make it into medical journals.

One user on r/kidney_stones wrote: “Woke up in the ER with potassium at 6.3 after using ‘Heart Salt’ for three weeks while on lisinopril.” Another, 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 users who self-identified as having kidney conditions mentioned their doctor told them to stop immediately after blood tests showed high potassium. These aren’t rare outliers. They’re predictable outcomes.

What about herbs and spices?

You don’t need potassium chloride to cut sodium. Herbs, spices, garlic, lemon juice, vinegar, and no-salt seasoning blends like Mrs. Dash can reduce sodium intake by 40-50%-without touching potassium levels. They’re safe, cheap, and don’t carry the metallic aftertaste that turns some people off potassium salt (a complaint in 28% of Amazon reviews).

And here’s the kicker: many people think “no added salt” means “no sodium.” It doesn’t. Processed foods still have tons of sodium. The real win? Cook from scratch. Use fresh ingredients. Flavor with herbs. That’s how you lower sodium without risking potassium overload.

What should you do?

If you’re on an ACE inhibitor or ARB:

1. Check your salt substitute label. If it says “potassium chloride,” stop using it.
2. Ask your doctor for a simple blood test to check your potassium level.
3. If your eGFR is below 60, avoid potassium substitutes entirely.
4. If your potassium is already above 4.5 mmol/L, don’t use them-even if your kidneys seem fine.
5. Replace salt substitutes with herbs, spices, or reduced-sodium broths.

The National Kidney Foundation says 63% of hyperkalemia cases in people on these drugs come from hidden dietary sources-not pills. That means your doctor might not even know you’re using a salt substitute unless you tell them.

Why aren’t these warnings clearer?

Only 3 out of 12 major salt substitute brands in the U.S. warn about interactions with ACE inhibitors or ARBs. The FDA doesn’t require it. Canada did-starting January 1, 2024. Their labels now say: “Contraindicated in patients taking ACE inhibitors.”

In the U.S., the Salt Substitute Council has voluntary labeling standards. But only six companies follow them, and audits happen only quarterly. That’s not safety. That’s luck.

The FDA proposed new rules in May 2024 to fix this. Final regulations are expected in mid-2026. Until then, you have to protect yourself.

What’s next?

New products are coming. NutraTech Solutions is testing a slow-release potassium formulation that might lower blood pressure without spiking serum levels. Results won’t be ready until late 2026.

But right now, the safest path is simple: if you’re on an ACE inhibitor or ARB, don’t use potassium-based salt substitutes. Period. There are better, safer ways to cut sodium. Your heart and kidneys will thank you.