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Best Potassium Supplements

Updated April 2023
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Best of the Best
Thorne Research Potassium Citrate
Thorne Research
Potassium Citrate
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Quality Supplement
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High-quality, effective potassium supplement in a manageable size that's easy to digest; approved by our nutrition expert.


Formulated to help cardiovascular health, skeletal strength, and urinary tract health. Quick absorption. Contains no gluten, yeast, dairy, soy, or fish. Made by a trusted brand in supplements.


Requires taking three capsules a day, which our expert notes might add to the pill burden of those taking other pills.

Best Bang for the Buck
NOW Foods Potassium Gluconate
NOW Foods
Potassium Gluconate
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Trusted Brand
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Quality tablets from a trusted brand that our expert notes are vegan-safe, but some find the size and texture hard to swallow.


Helps your body regulate fluid levels, muscle function, and nerve conductivity. Many found a decrease in leg cramping. Effective and budget-friendly.


Some find these tablets to be large and challenging to swallow.

Nature Made Potassium Gluconate Tablets
Nature Made
Potassium Gluconate Tablets
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A high-quality potassium supplement that supports the heart function and helps manage heart muscle activity.


Each tablet contains 90 mg of elemental potassium to support several functions of the body, including the heart and nerve functions. No colors added. Does not contain any yeast, starch, or preservatives. Gluten-free. USP-verified for purity.


Tablets are chalky; they may be tough to swallow and may stick to the back of the mouth.

Solaray Potassium Supplement
Potassium Supplement
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Small But Effective
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A potassium supplement that helps protect the muscles and central nervous system.


Helps keep the body's electrolyte levels in balance. Each bottle contains 200 capsules. Small capsules are easy to swallow. Each capsule contains 99 mg of potassium. More affordable than many comparable potassium supplements.


Sometimes causes stomach pain and nausea after initial use.

Nature's Bounty Potassium
Nature's Bounty
Potassium, 99 mg
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Simple Yet Solid
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Recommended by our nutrition expert for the widespread familiarity of the brand, this daily option is available at an affordable price.


Comes with 100 servings in caplet form. Each supplement delivers 99 mg of potassium and is designed to help with fluid balance. Made without unwanted ingredients such as artificial flavors, colors, and sweeteners. Is vegetarian-friendly and lab-tested.


May be difficult to swallow.

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BestReviews spends thousands of hours researching, analyzing, and testing products to recommend the best picks for most consumers. We only make money if you purchase a product through our links, and all opinions about the products are our own. About BestReviews  
BestReviews spends thousands of hours researching, analyzing, and testing products to recommend the best picks for most consumers. We buy all products with our own funds, and we never accept free products from manufacturers.About BestReviews 

We recommend these products based on an intensive research process that's designed to cut through the noise and find the top products in this space. Guided by experts, we spend hours looking into the factors that matter, to bring you these selections.

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Buying guide for Best potassium supplements

Potassium is a mineral that plays a crucial role in the human body. Most people don’t need to worry about a deficiency since it’s easy to get potassium from natural sources. However, some illnesses and conditions can contribute to a lack of potassium in the body. Without potassium, the body is prone to bouts of high blood pressure, nervous system dysfunction, and muscle spasms. Potassium is also critical for a healthy metabolism and plays an important role in digestion.

But high levels of the mineral are dangerous, so taking potassium supplements without first consulting a doctor is not advised. The BestReviews team wants to provide you with helpful information about this particular supplement to make sure it’s taken safely.

Below, you’ll find a guide that covers the causes of deficiency, symptoms that may be present when the body doesn’t have enough of this mineral, along with a handy list of natural sources of potassium.

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A diet with enough natural potassium sources can help protect you from high blood pressure, stroke, and salt sensitivity. Salt sensitivity is a condition in which blood pressure becomes elevated after ingesting salt. However, a potassium-rich diet is not the only factor that contributes to healthy blood pressure.

Who needs potassium supplements?

If you’re healthy, it’s very unlikely that you need to take a potassium supplement as part of your routine. Unless, for instance, you’re an athlete performing rigorous workouts on a regular basis, it’s likely that you consume enough potassium by way of your diet.

Potassium supplements should be taken on the recommendation of a healthcare professional and are often prescribed for individuals with impaired kidney function. Diagnosis of a deficiency should be made by your doctor.

Expert tip
Potassium is an electrolyte that the body needs to get from food and drinks. Since both low and high potassium is risky, I recommend consulting with a physician before taking a supplement. 
BestReviews Nutrition Expert

Signs of potassium deficiency

A few signs may point to a potassium deficiency. It’s not a good idea to supplement without having a clear picture of the cause of your symptoms. Don’t assume that because you’re experiencing any of the following symptoms that you’re deficient. These symptoms could be caused by other ailments. Speak to a health professional for an accurate diagnosis.

Mild deficiency

  • Fatigue

  • Cramping

  • Constipation

  • High blood pressure

  • Insomnia or poor-quality sleep

  • Concentration issues

Severe deficiency

  • May cause heart rhythm abnormalities in addition to the above symptoms

Causes of potassium deficiency

There are several reasons why your body might be deficient in potassium.

  • Kidney malfunction (a common cause of potassium deficiency)

  • Hyperthyroidism

  • Poor diet (could also result in a number of vitamin or mineral deficiencies)

  • Frequent laxative use

  • Diabetes

  • Alcoholism

  • Antibiotic use or taking other potassium-depleting medication

  • Dehydration

Expert tip
If you have a severe deficiency of potassium (hypokalemia), your doctor might prescribe you IV treatment. Signs of hypokalemia include extreme fatigue, irregular heartbeat, muscle spasms/weakness/cramping, as well as constipation, nausea, or vomiting. 
BestReviews Nutrition Expert

Types of potassium supplements

Different types of potassium supplements are absorbed differently by the body. Your doctor will prescribe the right kind for you and your particular condition. Some forms of potassium in supplement form include potassium gluconate, chloride, aspartate, chelate, phosphate, bicarbonate, citrate, and orotate.

Potassium supplement factors to consider

There are a few things to consider before heading to the supplement aisle at your local pharmacy.

Talk to your doctor

Potassium supplements can be harmful in high doses and, in some cases, taking too much of this mineral can be fatal. Speak to your doctor before purchasing and taking this supplement. Your doctor can help determine whether a deficiency is genuinely present and what form of potassium to take as part of your treatment. A deficiency could also be the result of a more severe condition, which is best diagnosed by a healthcare practitioner. Self-diagnosis is not recommended.

Drug interactions

Potassium supplements may interact with a variety of medications. Some medications can inhibit absorption, while others do the opposite and cause a buildup of potassium in the system.


Your physician will determine the right dosage for you. The recommended daily intake for potassium is 4,700 mg for healthy adults. The number is slightly higher for women who are breastfeeding. Most individuals should not have an issue getting enough potassium from their diet. There is no upper limit recommended by the FDA, but it’s well documented that high doses of potassium supplementation can lead to heart problems that in some cases prove fatal. Overdose is extremely unlikely to occur when potassium is ingested solely via food sources, however.


Potassium supplements come in capsules, tablets, liquids, and powders. Potassium can also be injected into the bloodstream by a qualified physician.

"Some cereals and other foods are fortified with vitamins and minerals like potassium. However, the potassium found in these enriched foods is not as easily absorbed by the body."

Potassium supplement prices

Potassium supplements are relatively inexpensive, ranging from $0.02 to $0.25 per capsule or gram of powder.


Potassium supplements that cost under $0.10 per pill typically offer a lower dosage of the mineral.


Supplements that cost from $0.10 to $0.15 per pill feature a higher dosage per capsule and may contain multiple types of potassium.


Supplements on the higher end of the price spectrum, up to $0.25 per pill, typically include potassium as part of an electrolyte replacement and are often targeted toward athletes. Pricier options may also be marketed as organic.

Other sources of potassium

Eating a variety of fruits and vegetables is the best way to make sure you’re getting enough potassium. Here are some sources of the mineral that you can find easily at your local grocery store or maybe even in your kitchen right now.

  • Avocados

  • Bananas

  • Beans and lentils

  • Beet greens

  • Potatoes (unpeeled)

  • Squash

  • Sweet potatoes

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Did you know?
The condition known as hyperkalemia is caused by elevated potassium levels in the bloodstream.


  • Take supplements with a beverage or food. Potassium supplements can cause stomach irritation in some people, which is why it’s important to ingest them with water or another beverage. Taking potassium with food or right after eating is also advised. You could feel nauseated or your stomach could be upset after taking potassium.

  • Use and store supplements as directed. Unless advised by your doctor, it’s not recommended that you crush tablets or capsules. Keep potassium supplements in a cool, dry place away from direct sunlight. This is especially important for liquid forms of potassium.

  • Watch out for low-sodium foods. Some low-sodium foods contain additional potassium and should not be eaten in addition to supplements.

  • Don’t take a potassium supplement if you’re taking a multivitamin. There are a variety of multivitamins that include low doses of potassium. Unless you have a known potassium deficiency, it’s most cost effective and convenient to take a single capsule daily.
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Athletes with demanding training schedules might have a greater need for a potassium supplement.


Q. Is it safe to take potassium supplements?

A. This supplement is fine In small doses since the recommended daily dose is fairly high. The trouble is that overdoing it can be dangerous. If you take medications, potassium supplements could interact with them, too. Those with heart problems or diabetes should not take potassium supplements. Potassium is not a supplement that should be taken without speaking to your doctor first.

Expert tip
If you are not keen on taking a supplement, these foods are high in potassium: white beans, potatoes, beets, parsnips, spinach, swiss chard, tomatoes, oranges, and bananas. 
BestReviews Nutrition Expert

Q. Is there anyone who should avoid potassium supplements?

A. Anyone on blood pressure medication and individuals with kidney or heart problems should not take OTC potassium supplements without consulting a healthcare practitioner.

Q. How do I know how much to take?

A. For adults, the daily recommended amount of potassium is 4,700 mg. You should not take that amount in supplements, however. Intake from food should be sufficient unless you have a condition or you’re taking medication that causes potassium deficiency. Ingesting high doses of this supplement can be dangerous. Bottles of potassium sold over the counter come in small doses, typically less than 100 mg, to prevent overdosing and harmful side effects. Doses under 100 mg are safe in most cases. Don’t take multiple doses without first consulting your doctor.

Q. Can I take potassium supplements with other medications?

A. Some medications may deplete your body’s potassium, while others can raise the levels of this important mineral. If you’re on medication, always talk to your doctor before taking a supplement such as potassium.

Q. Can I buy potassium supplements over the counter?

A. Yes. But in the United States, the supplement is regulated so that doses sold over the counter typically do not exceed 100 mg, a small fraction of the daily recommended amount. This limit helps prevent dangerous side effects of over-supplementation. If you are truly deficient as a result of an illness or condition, you would need to take a lot of OTC capsules or tablets. Severe deficiencies are therefore best diagnosed and treated by your doctor.

Q. Do supplements expire?

A. Not technically. An expiration date on a supplement bottle simply indicates the time when potency may start to decline. Good news: minerals like potassium don’t degrade as quickly as vitamins, so they have a longer shelf life. Using these types of products after the expiration date isn’t dangerous, but the supplement may not be as effective as it once was. The exception to the rule is with liquids. Stored incorrectly, these can rapidly turn rancid.

Q. Is it safe to take potassium supplements while breastfeeding?

A. The mineral does pass through breast milk, so if you’re considering taking the supplement, please talk to your doctor.