Q: There’s a bright yellow sticker on my prescription bottle suggesting I eat a banana or drink a glass of orange juice every day while on that medicine. If I do that, can I stop taking my huge potassium pills every day?
You must be talking about the little label that says “It may be advisable to drink a full glass of orange juice or eat a banana daily while taking this medication.” It’s meant to encourage you to eat foods that contain potassium.
One of the most important minerals in your body is potassium. Potassium helps you regulate the acid-base balance in your blood, make proteins from amino acids, build muscle and balance your heart’s electrical activity. Some medicines do what they do by pulling water and minerals like sodium and potassium out of your body. Because they make you urinate a lot more than usual they are also called “water pills” or diuretics. Pharmacists add this particular sticker to prescription bottles of “water pills” to encourage getting more potassium in your diet.
It’s especially important to keep your potassium level balanced if you take the heart medicine digoxin, as too much or too little potassium in your blood could trigger abnormal heart rhythms with serious, even deadly results. Your doctor can track your potassium level by testing your blood and if it’s too low give you supplemental potassium.
How does the potassium in your blood drop too low? From the foods you do or do not eat, by vomiting, or by taking prescription diuretics. Diuretics are medicines that are also called “water pills” because they remove water from your body by making you urinate more frequently. Diuretics such as furosemide, hydrochlorothiazide, and chlorthalidone work by removing fluid from your lungs and reducing swelling in your hands or feet. The medicine pulls water out of your body but along with it goes sodium, potassium and magnesium. A diuretic can be combined with another medicine to prevent excess potassium loss and balance things out.
Potassium is measured in two ways: by mg and by mEq. Most prescription forms of potassium are labeled as mEq and are available as either 10mEq or 20mEq tablets.
Depending on our food choices, we take in between 40 to 150mEq potassium every day. Eating a medium-sized banana gives you 12mEq of potassium. An 8-ounce glass of orange juice contains 7mEq. Leafy green vegetables and foods that grow on vines are particularly good sources of potassium, as are milk and yogurt. One potato with the skin has 21mEq potassium. More information on potassium content of foods go to is available at http://www.health.gov/dietaryguidelines/dga2005/document/html/appendixB.htm#appB1.
Many prescription potassium pills are BIG and hard to swallow, leading some folks try non-prescription versions instead. One common non-prescription form is potassium gluconate with 595mg (99 mg of potassium) in each tablet.
How does 99mg of potassium compare to the prescription strength of 10mEq? In each mEq, there is 39mg of potassium, whether it comes as potassium chloride or gluconate. One potassium gluconate tablet with 595mg of potassium gluconate gives you 99mg of potassium or 2.5mEq. It takes four tablets of non-prescription potassium gluconate to equal the potassium in one prescription-only tablet of 10mEq potassium chloride.
Getting enough potassium is important, but not everyone needs more of it. People with kidney problems do not eliminate potassium easily, and taking certain heart medicines like lisinopril or spironolactone can increase the amount of potassium in your body up to dangerous levels, especially you are also taking a potassium supplement.
Do you have to drink a full glass of orange juice or eat a banana every day for your potassium? Not really; in fact, the potassium found in foods doesn’t work as well as potassium chloride when correcting low potassium levels from vomiting or taking a diuretic. Salt substitutes such as NoSalt® or Morton Salt Substitute® are a particularly concentrated source of potassium, containing 15-20mEq in each ¼ teaspoonful. Switching from using table salt (containing sodium chloride) to a salt substitute containing potassium chloride can dramatically increase your potassium intake.
People getting kidney dialysis should avoid foods with high amounts of potassium and avoid using salt substitutes because they cannot easily remove potassium from their bodies. For the rest of us, using a salt substitute is one of the least expensive ways to get more potassium.
