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Kalexate

Generic Name: sodium polystyrene sulfonate (SOE dee um pol ee STEER een SUL foe nate)
Brand Name: Kalexate, Kayexalate, Kionex

Medically reviewed on March 7, 2018

What is Kalexate?

Kalexate binds itself to potassium in your digestive tract. This helps prevent your body from absorbing too much potassium.

Kalexate is used to treat high levels of potassium in the blood, also called hyperkalemia.

Kalexate works differently from other medicines because it passes into your intestines without being absorbed into your blood stream.

Kalexate may also be used for purposes not listed here.

Important Information

You should not use Kalexate if you have low potassium levels or a bowel obstruction.

Do not give this medicine orally (by mouth) to a newborn baby.

Avoid taking other medicines by mouth within 3 hours before or 3 hours after you take Kalexate (or 6 hours before/after if you have slow digestion).

Before taking this medicine

You should not use Kalexate if you are allergic to it, or if you have:

  • low potassium levels (hypokalemia); or

  • a bowel obstruction.

Tell your doctor if you have ever had:

  • heart disease or high blood pressure;

  • a weak immune system caused using certain medicine;

  • severe constipation or other bowel problems;

  • kidney disease (or if you are on dialysis);

  • an electrolyte imbalance (such as low levels of potassium, calcium, or magnesium in your blood);

  • fluid retention;

  • severe burns;

  • a bowel disorder, or surgery on your intestines;

  • if you are dehydrated; or

  • if you are on a low-salt diet.

Because Kalexate is not absorbed into the blood stream, this medicine is not expected to be harmful during pregnancy or while nursing a baby. Tell your doctor if you are pregnant or breast-feeding.

How is Kalexate given?

Follow all directions on your prescription label and read all medication guides or instruction sheets. Use the medicine exactly as directed.

Kalexate can be given as a liquid by mouth, through a stomach feeding tube, or as a rectal enema.

Do not give Kalexate orally (by mouth) to a newborn baby. Do not use the medicine orally or rectally in a baby who has slow digestion caused by surgery or by using other medicines.

To give this medicine orally: Mix the Kalexate powder with water, or with honey or jam to make it taste better. Avoid inhaling the oral powder while you are preparing a dose.

Do not mix the powder with any juice or other liquid that contains potassium, such as orange juice.

The rectal enema form of this medicine is usually given by a healthcare professional. The enema will be inserted slowly while you are lying down. You may need to hold in the enema for up to several hours. The Kalexate enema is usually followed with a second cleansing enema.

You will need frequent medical tests to help your doctor determine how long to treat you with Kalexate.

Keep using this medicine even if you feel fine. Hyperkalemia often has no symptoms that you will notice until your potassium levels are very low.

Store at room temperature away from moisture and heat.

What happens if I miss a dose?

Use the medicine as soon as you can, but skip the missed dose if it is almost time for your next dose. Do not use two doses at one time.

What happens if I overdose?

Seek emergency medical attention or call the Poison Help line at 1-800-222-1222.

What should I avoid while using Kalexate?

Avoid using antacids or laxatives without your doctor's advice. Antacids or laxatives can make Kalexate less effective, or cause serious side effects.

Do not use potassium supplements, calcium supplements, or salt substitutes while you are taking Kalexate, unless your doctor has told you to.

Avoid eating or drinking anything that contains sorbitol (a fruit sugar often used as a sweetener in chewing gum, diet drinks, baked goods, or frozen desserts).

Kalexate side effects

Get emergency medical help if you have signs of an allergic reaction: hives; difficult breathing; swelling of your face, lips, tongue, or throat.

Stop using Kalexate and call your doctor at once if you have:

  • stomach pain, rectal pain;

  • severe constipation, severe stomach pain, bloating;

  • fever, chills, vomiting;

  • confusion, thinking problems, feeling irritable;

  • low potassium--leg cramps, constipation, irregular heartbeats, fluttering in your chest, increased thirst or urination, numbness or tingling, muscle weakness or limp feeling;

  • low calcium levels--muscle spasms or contractions, numbness or tingly feeling (around your mouth, or in your fingers and toes); or

  • signs of stomach bleeding--bloody or tarry stools, coughing up blood or vomit that looks like coffee grounds.

Common side effects may include:

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

See also: Side effects (in more detail)

What other drugs will affect Kalexate?

Kalexate can make it harder for your body to absorb medicines you take by mouth. Avoid taking other medicines within 3 hours before or 3 hours after you take this medicine.

  • If you have a condition that slows your digestion, avoid taking other medicines by mouth within 6 hours before or 6 hours after you take Kalexate.

Tell your doctor about all your other medicines. Some may affect Kalexate, especially:

  • digoxin, digitalis;

  • lithium;

  • thyroxine; or

  • drugs that weaken the immune system such as cancer medicine, steroids, and medicines to prevent organ transplant rejection.

This list is not complete. Other drugs may affect Kalexate, including prescription and over-the-counter medicines, vitamins, and herbal products. Not all possible drug interactions are listed here.

Further information

Remember, keep this and all other medicines out of the reach of children, never share your medicines with others, and use this medication only for the indication prescribed.

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.

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