Slow-K (potassium chloride)

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Brand Name

Slow-K {Novartis}

Generic Name

potassium chloride, pronounced poe TASS ee um Klo ride


What is Slow-K?

Slow-K is an extended release tablet that helps to prevent or treat low blood levels of potassium, which is also called hypokalemia. You may have low potassium levels due to a disease, from taking certain medicines or after a prolonged illness with diarrhea or vomiting.

Slow-K may also be used for purposes not indicated in this medication guide.


Key Facts About Slow-K

Slow-K contains potassium chloride, and potassium is an important mineral for your body. Potassium is needed for several functions of your body, especially the beating of your heart.

Potassium is found in many foods, including squash, baked potatoes (with the skin on), spinach, lentils, broccoli, brussel sprouts, zucchini, navy beans, raisins, watermelon, kidney beans, orange juice, bananas, cantaloupe, and low-fat milk or yogurt. While taking Slow-K you should be careful when consuming potassium-rich foods, and only eat the daily amounts recommended by your doctor.

Slow-K is a part of a complete program of treatment that your doctor may have prescribed for you, which can include diet, exercise, and weight control.

You should not stop taking Slow-K suddenly. Tell your doctor if you wish to stop taking Slow-K and he or she will help you stop safely.

While you are taking Slow-K your doctor may have you undergo blood tests or an electrocardiograph (sometimes called an EKG) to measure the electrical activity of your heart. These tests will help your doctor be sure that Slow-K is helping your condition and not hurting you.

Tell your doctor if you are pregnant or plan to become pregnant. Slow-K is in FDA pregnancy category C. Slow-K is not known to harm an unborn baby. You may have a need for an increased dose of Slow-K if you are pregnant. Talk to your doctor about your Slow-K intake. If you are breast-feeding you should ask your doctor about taking Slow-K. We do not know if Slow-K may affect a breast-feeding baby.


Before You Take Slow-K

If you are allergic topotassium chloride, or if you have high levels of potassium in your blood (hyperkalemia) you should not take Slow-K.

If you have kidney disease, kidney failure, Addison’s disease (an adrenal gland disorder) or a large tissue injury such as a severe burn you should not take Slow-K.

Before taking Slow-K, tell your doctor if you are taking a “potassium-sparing” diuretic (water pill) like amiloride (Midamor, Moduretic), spironolactone (Aldactone, Aldactazide) or triamterene (Dyrenium, Dyazide, Maxzide).

Let your doctor know if you have high blood pressure, heart disease, chronic diarrhea (such as ulcerative colitis or Crohn’s disease), or are severely dehydrated before taking Slow-K.

If you have a blockage in your stomach or intestines you should inform your doctor before starting treatment with Slow-K.


Slow-K Drug Interactions

You should inform your doctor if you are taking any of the following:

  • ACE inhibitors like benazepril (Lotensin), captopril (Capoten), fosinopril (Monopril), enalapril (Vasotec), lisinopril (Prinivil, Zestril), moexipril (Univasc), perindopril (Aceon), quinapril (Accupril), ramipril (Altace) and trandolapril (Mavik)
  • bronchodilators like ipratroprium (Atrovent) and tiotropium (Spiriva)
  • digoxin (digitalis, Lanoxin)
  • diuretics (water pills) like bumetanide (Bumex), chlorothiazide (Diuril), chlorthalidone (Hygroton, Thalitone), ethacrynic acid (Edecrin), furosemide (Lasix), hydrochlorothiazide (HCTZ, HydroDiuril, Hyzaar, Lopressor, Vasoretic, Zestoretic), indapamide (Lozol), metolazone (Mykrox, Zarxolyn) and torsemide (Demadex)
  • eplerenone (Inspra)
  • quinidine (Quinaglute, Quinidex, Quin-Release)

Other drugs you take that are not listed may interact with Slow-K. You should tell your doctor about all of the medications you use. This includes prescription drugs, vitamins, supplements and herbal products, and over the counter medications. You should not begin taking a new medication without telling your doctor first.


Directions for Taking Slow-K

You should take Slow-K exactly as it is prescribed by your doctor. Your doctor may change your dose to make sure that you get the best results from Slow-K. You should follow the instructions on your prescription label and not take Slow-K for longer than recommended by your doctor, or in larger or smaller doses.

Slow-K usual dosage is a range of 2 to 6 tablets daily. It is recommended not to exceed 12 tablets in 24 hours. The daily dose should be divided throughout the day to prevent side effects.

Slow-K should be taken with food or right after a meal.

Slow-K should be taken with a full glass of water or another liquid and you should remain sitting upright or standing for 15 to 30 minutes after taking the medication.

You should not break, chew, crush or suck on a Slow-K tablet. You should swallow the tablet whole. If you suck on a potassium tablet it can irritate your mouth or throat.

The Slow-K tablet is a wax matrix that releases the medication slowly away from the bowel walls to prevent side effects. This wax matrix tablet may be excreted in a softened form in a bowel movement after it releases the medication.

Slow-K needs to be stored at room temperature, and away from light, moisture and heat.

If you miss a dose of Slow-K you should take the missed dose as soon as you remember. Do not take extra medicine to make up the missed dose.


Slow-K Side Effects

If you experience any of the following adverse effects you should stop taking Slow-K and seek emergency medical help immediately:

  • allergic reaction symptoms like breathing difficulties, hives, and swelling of your face, lips, throat or tongue
  • anxiety and confusion
  • black, bloody or tarry stools
  • coughing up blood or vomit that looks like coffee grounds
  • faint feeling
  • extreme thirst
  • heartbeats that are uneven
  • leg discomfort
  • muscle weakness or a limp feeling
  • numbness or tingly feeling in your hands or feet, or around your mouth
  • stomach bloating/abdominal distension with pain, stomach pain that is severe with diarrhea and vomiting
  • urination that is increased

Signs of too much potassium in your body;

  • Nausea
  • Vomiting
  • Diarrhea
  • Abdominal cramping
  • Tingling, prickling of skin/numbness
  • Reduced or absence of reflexes
  • Convulsions
  • Trouble breathing
  • Abdominal distension
  • Changes in heartbeat
  • Low blood pressure or shock

More common side effects of Slow-K may include:

  • diarrhea and upset stomach (mild)
  • nausea (mild)
  • gas/flatulence.
  • tingling in your hands and feet that is slight

It should be noted that this is not a complete list of possible side effects of Slow-K. You should contact your physician for a complete list and medical advice regarding these effects.

Slow-K Description and Dosing

Slow-K is available as a 600 mg tablet, round, buff-colored, sugar-coated and imprinted with Slow-K.

Slow-K should be approved by your doctor before you begin taking it, and you should not change your dose without talking to your physician first.

If you suspect that you have overdosed with Slow-K you should seek emergency help immediately.


Ingredients in Slow-K

The primary active ingredient in Slow-K is potassium chloride. Inactive ingredients are Acacia, cetostearyl alcohol, gelatin, iron oxide, magnesium stearate, parabens, polyvinyl-pyrrolidone, sodium benzoate, starch, sucrose, talc, and titanium dioxide.

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The information contained in this drug guide is intended as an educational resource only. This guide is not exhaustive and does not contain all available information about this drug.This guide is not intended as medical advice for individual conditions or treatment.

The information provided in this guide does not replace the need for the advice and services of medical professionals or the need for medical examination. Always talk to your physician or pharmacist before taking any prescription medication or over the counter drugs (including any supplements) or before making any changes to your treatment. Only your doctor, nurse or pharmacist can provide you with safe and effective advice regarding your drug treatment.

The use of the information in this guide is at your sole risk. This information is provided "AS IS" with no warranties to accuracy or timeliness.

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