Sodium/potassium/magnesium sulfate solution is used to clean out the intestines before a certain bowel exam procedure (colonoscopy). It is a laxative that works by drawing large amounts of water into the colon. This causes watery bowel movements. Clearing stool from the intestines helps your doctor to better examine the intestines during your procedure.

How to use Suprep

Read the Medication Guide and Instructions for Use provided by your pharmacist before you start using this product and each time you get a refill. If you have any questions, ask your doctor or pharmacist.

Follow any special diet instructions provided by your doctor. Usually, you may have a small breakfast or only clear liquids on the day before your procedure. After breakfast, you may only drink clear liquids until after your procedure. Do not drink milk or alcoholic beverages or eat/drink anything colored red or purple. To prevent becoming dehydrated, drink as much clear liquid as you can before, during, and after drinking this medication unless otherwise directed by your doctor.

Do not take any other medications by mouth within 1 hour of starting to drink the mixture. Ask your doctor or pharmacist if you are not sure when to take your other medications.

Use this product as directed by your doctor, usually one dose the evening before the colonoscopy and the second dose the next day in the morning. The dosage is based on your age and medical condition.

Before using this product, pour the contents into the mixing container as directed by the manufacturer. Add cool water, mix, and drink all of the mixture. After drinking the mixture, drink 2 additional containers filled with water over the next hour. Be sure to finish drinking all of the mixture and required water at least 2 hours before your procedure, or as directed.

Ask your doctor or pharmacist if you have any questions about how to mix or take this product or what to expect after taking this product.

Watery bowel movements usually begin about 1 hour after you drink the mixed liquid. The bowel movements can be very large and watery.

Side Effects

Very watery bowel movements are expected with this medication. Nausea, vomiting, bloating, or stomach/abdominal cramping may occur. If any of these effects last or get worse, tell your doctor or pharmacist promptly.

Remember that this medication has been prescribed because your doctor has judged that the benefit to you is greater than the risk of side effects. Many people using this medication do not have serious side effects.

This medication can cause your body to lose too much fluid and salts (dehydration, electrolyte problems). Tell your doctor right away if you have any of these serious side effects: severe dizziness, fainting, fast/irregular heartbeat, trouble keeping liquids down, prolonged vomiting, headache, seizure.

Tell your doctor right away if you have any serious side effects, including: stomach/abdominal pain that is severe or doesn't go away, signs of kidney problems (such as change in the amount of urine), bloody stools, rectal bleeding.

A very serious allergic reaction to this drug is rare. However, get medical help right away if you notice any symptoms of a serious allergic reaction, including: rash, itching/swelling (especially of the face/tongue/throat), severe dizziness, trouble breathing.

This is not a complete list of possible side effects. If you notice other effects not listed above, contact your doctor or pharmacist.

In the US -

Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088 or at

In Canada - Call your doctor for medical advice about side effects. You may report side effects to Health Canada at 1-866-234-2345.


Before taking this medication, tell your doctor or pharmacist if you have any allergies. This product may contain inactive ingredients, which can cause allergic reactions or other problems. Talk to your pharmacist for more details.

Before using this medication, tell your doctor or pharmacist your medical history, especially of: blocked intestines (gastrointestinal obstruction), hole in the intestines, severe ulcers/swelling of the colon (ulcerative colitis), severe infection in the intestines (such as toxic colitis, toxic megacolon), stomach/intestines that empty slowly or are not moving (gastric retention, ileus), trouble swallowing, trouble keeping food down (regurgitation), history of breathing food/other substances into the lungs (aspiration), gout, heart problems (such as irregular heartbeat, chest pain, heart failure), kidney problems, seizure, regular use of alcohol or other sedatives.

Before having surgery, tell your doctor or dentist about all the products you use (including prescription drugs, nonprescription drugs, and herbal products).

During pregnancy, this medication should be used only when clearly needed. Discuss the risks and benefits with your doctor.

It is unknown if this drug passes into breast milk. Consult your doctor before breastfeeding.


See also How to Use section.

Drug interactions may change how your medications work or increase your risk for serious side effects. This document does not contain all possible drug interactions. Keep a list of all the products you use (including prescription/nonprescription drugs and herbal products) and share it with your doctor and pharmacist. Do not start, stop, or change the dosage of any medicines without your doctor's approval.

Some products that may interact with this drug include drugs that can change the amount of water, sodium, or potassium in your body, such as: heart/blood pressure medications called ARBs (such as valsartan), heart/blood pressure medications called ACE inhibitors (such as captopril, enalapril), nonsteroidal anti-inflammatory drugs - NSAIDs (such as ibuprofen, naproxen), "water pills" such as thiazide diuretics.

Do not take/use other laxatives while taking this product.

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If someone has overdosed and has serious symptoms such as passing out or trouble breathing, call 911. Otherwise, call a poison control center right away. US residents can call 1-800-222-1222. Canada residents can call 1-844-764-7669.

Notes Notes

Do not share this medication with others.

Lab tests (such as sodium, potassium levels) may be done before or after taking this medication. Keep all medical and lab appointments. Consult your doctor for more details.

Missed Dose Missed Dose

If you are unable to drink all of the solution and water as directed, call your doctor right away. Your test may need to be rescheduled.

Storage Storage

Store the unmixed container at room temperature away from light and moisture. Do not store in the bathroom. Keep all medications away from children and pets.

Do not flush medications down the toilet or pour them into a drain unless instructed to do so. Properly discard this product when it is expired or no longer needed. Consult your pharmacist or local waste disposal company.


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Selected from data included with permission and copyrighted by First Databank, Inc. This copyrighted material has been downloaded from a licensed data provider and is not for distribution, except as may be authorized by the applicable terms of use.

CONDITIONS OF USE: The information in this database is intended to supplement, not substitute for, the expertise and judgment of healthcare professionals. The information is not intended to cover all possible uses, directions, precautions, drug interactions or adverse effects, nor should it be construed to indicate that use of a particular drug is safe, appropriate or effective for you or anyone else. A healthcare professional should be consulted before taking any drug, changing any diet or commencing or discontinuing any course of treatment.