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URL of this page: https://medlineplus.gov/druginfo/meds/a619013.html

Magnesium Sulfate, Potassium Sulfate, and Sodium Sulfate

pronounced as (mag nee' zee um) (sul' fate)

Why is this medication prescribed?

Magnesium sulfate, potassium sulfate, and sodium sulfate is used to empty the colon (large intestine, bowel) before a colonoscopy (examination of the inside of the colon to check for colon cancer and other abnormalities) in adults and children 12 years of age and older so that the doctor will have a clear view of the walls of the colon. Magnesium sulfate, potassium sulfate, and sodium sulfate is in a class of medications called osmotic laxatives. It works by causing watery diarrhea so that the stool can be emptied from the colon.

How should this medicine be used?

Magnesium sulfate, potassium sulfate, and sodium sulfate comes as a comes as a solution (liquid) (Suprep®) and as tablets (Sutab®) to take by mouth. The first dose is usually taken the night before the colonoscopy and the second dose taken the morning of the procedure. Your doctor will tell you exactly when you should take your medication. Follow the directions on your prescription label carefully, and ask your doctor or pharmacist to explain any part you do not understand. Take magnesium sulfate, potassium sulfate, and sodium sulfate exactly as directed. Do not take more or less of it than prescribed by your doctor.

To prepare for your colonoscopy, you may not eat any solid food or drink milk beginning the day before the procedure. You should only have clear liquids during this time. Examples of clear liquids are water, light colored fruit juice without pulp, clear broth, coffee or tea without milk, flavored gelatin, popsicles, and soft drinks. Do not drink alcoholic beverages or any liquid that is red or purple. Ask your doctor if you have any questions about which liquids you may drink before your colonoscopy. Tell your doctor if you have trouble drinking clear liquids.

If you are taking the solution (Suprep®), you will need to mix the medication solution with water right before you take it. If you swallow the solution without mixing it with water, there is a greater chance that you will experience unpleasant or dangerous side effects. To prepare each dose of your medication, pour the contents of one bottle of magnesium sulfate, potassium sulfate, and sodium sulfate solution into the dosing container that was provided with the medication and fill the container with water up to the line (16 ounces, 480 mL or 12 ounces, 300 mL) that is marked on the cup. Drink the entire mixture right away. You will take your first dose on the evening before your colonoscopy. After you take this dose, you will need to drink two containers (16 ounces, 480 mL or 12 ounces, 300 mL) of water within the next hour before you go to bed. You will take your second dose the next morning before your colonoscopy is scheduled. After you take the second dose, you will need to drink two containers (16 ounces, 480 mL or 12 ounces, 300 mL) of water within the next hour, but you should finish all the drinks at least 2 hours before your colonoscopy.

If you are taking the tablets (Sutab®), each dose is 12 tablets. You will take your first dose (12 tablets) the evening before your colonoscopy is scheduled and your second dose (12 tablets) the following morning before your colonoscopy is scheduled. For each dose, you will need to fill the container that was provided with water up to the line (16 ounces, 480 mL) that is marked on the cup. You should take each tablet with a sip of water and then drink the entire contents of the cup over 15 to 20 minutes. Approximately 1 hour after you take a dose (12 tablets), you will need to drink one 16-ounce container of water over 30 minutes; 30 minutes after finishing the second container of water, you will need to drink another 16-ounce container of water over 30 minutes. After you take the second dose (12 tablets), you should finish all the drinks at least 2 hours before your colonoscopy.

You will have many bowel movements during your treatment with magnesium sulfate, potassium sulfate, and sodium sulfate. Be sure to stay close to a toilet from the time you take your first dose of the medication until the time of your colonoscopy appointment. Ask your doctor about other things you can do to stay comfortable during this time.

Your doctor or pharmacist will give you the manufacturer's patient information sheet (Medication Guide) when you begin treatment with this medication. Read the information carefully and ask your doctor or pharmacist if you have any questions. You can also visit the Food and Drug Administration (FDA) website (https://www.fda.gov/Drugs/DrugSafety/ucm085729.htm) or the manufacturer's website to obtain the Medication Guide.

Other uses for this medicine

This medication may be prescribed for other uses; ask your doctor or pharmacist for more information.

What special precautions should I follow?

Before taking magnesium sulfate, potassium sulfate, and sodium sulfate,

  • tell your doctor and pharmacist if you are allergic to magnesium sulfate, potassium sulfate, or sodium sulfate, any other medications, or any of the ingredients in magnesium sulfate, potassium sulfate, and sodium sulfate oral solution or tablets. Ask your pharmacist or check the Medication Guide for a list of the ingredients.
  • tell your doctor and pharmacist what prescription and nonprescription medications, vitamins, nutritional supplements, and herbal products you are taking or plan to take while taking magnesium sulfate, potassium sulfate, and sodium sulfate. Your doctor may need to change the doses of your medications or monitor you carefully for side effects.
  • do not take any other laxatives during your treatment with magnesium sulfate, potassium sulfate, and sodium sulfate.
  • if you take any medications by mouth, take them at least 1 hour before you start taking magnesium sulfate, potassium sulfate, and sodium sulfate. If you are taking chlorpromazine, ciprofloxacin (Cipro), delafloxacin (Baxdela), demeclocycline, digoxin (Lanoxin), doxycycline (Acticlate, Doryx, Oracea, Vibramycin, others), gemifloxacin (Factive), iron supplements, levofloxacin, minocycline (Minocin, Minolira, Solodyn, others), moxifloxacin (Avelox), ofloxacin, penicillamine (Cupramine, Depen), or tetracycline (Achromycin V, in Pylera), take them at least 2 hours before you start or 6 hours after you take a dose of magnesium sulfate, potassium sulfate, and sodium sulfate solution or tablets.
  • tell your doctor if you have or have ever had a blockage in your stomach or intestine, an opening in the wall of your stomach or intestine, toxic megacolon (life-threatening widening of the intestine), or any condition that causes problems with the emptying of your stomach or intestine. Your doctor may tell you not to take magnesium sulfate, potassium sulfate, and sodium sulfate.
  • tell your doctor if you have been drinking large amounts of alcohol or taking medications for anxiety or seizures but are now decreasing your use of these substances. Also tell your doctor if you have recently had a heart attack and if you have or have ever had heart failure, an irregular heartbeat, an enlarged heart, a prolonged QT interval (a rare heart problem that may cause irregular heartbeat, fainting, or sudden death), gout, seizures, a low level of sodium, magnesium, potassium, or calcium in your blood, inflammatory bowel disease (conditions such as Crohn's disease (a condition in which the body attacks the lining of the digestive tract, causing pain, diarrhea, weight loss, and fever) and ulcerative colitis (a condition which causes swelling and sores in the lining of the colon [large intestine] and rectum) that cause swelling and irritation in all or part of the intestine), difficulty swallowing, gastric reflux (condition in which backward flow of acid from the stomach causes heartburn and possible injury to the esophagus) or kidney disease.
  • tell your doctor if you are pregnant, plan to become pregnant, or are breastfeeding.

What special dietary instructions should I follow?

Your doctor will tell you what you may eat and drink before, during, and after your treatment with magnesium sulfate, potassium sulfate, and sodium sulfate. Follow these directions carefully.

What should I do if I forget a dose?

Call your doctor if you forget or are unable to take this medication exactly as directed.

What side effects can this medication cause?

Magnesium sulfate, potassium sulfate, and sodium sulfate may cause side effects. Tell your doctor if any of these symptoms are severe or do not go away:

  • stomach pain or cramps
  • bloating
  • nausea
  • headache

Some side effects can be serious. If you experience any of these symptoms, call your doctor immediately or get emergency medical treatment:

  • seizures
  • fainting
  • feeling confused
  • vomiting, especially if you can't keep down the fluids that you need for your treatment
  • difficulty swallowing
  • rectal bleeding
  • deceased urination
  • dizziness
  • irregular heartbeat
  • sudden, severe pain in one or more joints

Magnesium sulfate, potassium sulfate, and sodium sulfate may cause other side effects. Call your doctor if you have any unusual problems while taking this medication.

If you experience a serious side effect, you or your doctor may send a report to the Food and Drug Administration's (FDA) MedWatch Adverse Event Reporting program online (https://www.fda.gov/Safety/MedWatch) or by phone (1-800-332-1088).

What should I know about storage and disposal of this medication?

Keep this medication in the container it came in, tightly closed, and out of reach of children. Store it at room temperature and away from excess heat and moisture (not in the bathroom).

It is important to keep all medication out of sight and reach of children as many containers (such as weekly pill minders and those for eye drops, creams, patches, and inhalers) are not child-resistant and young children can open them easily. To protect young children from poisoning, always lock safety caps and immediately place the medication in a safe location — one that is up and away and out of their sight and reach. https://www.upandaway.org

Unneeded medications should be disposed of in special ways to ensure that pets, children, and other people cannot consume them. However, you should not flush this medication down the toilet. Instead, the best way to dispose of your medication is through a medicine take-back program. Talk to your pharmacist or contact your local garbage/recycling department to learn about take-back programs in your community. See the FDA's Safe Disposal of Medicines website (https://goo.gl/c4Rm4p) for more information if you do not have access to a take-back program.

In case of emergency/overdose

In case of overdose, call the poison control helpline at 1-800-222-1222. Information is also available online at https://www.poisonhelp.org/help. If the victim has collapsed, had a seizure, has trouble breathing, or can't be awakened, immediately call emergency services at 911.

What other information should I know?

Keep all appointments with your doctor and the laboratory. Your doctor may order certain lab tests to check your body's response to magnesium sulfate, potassium sulfate, and sodium sulfate.

It is important for you to keep a written list of all of the prescription and nonprescription (over-the-counter) medicines you are taking, as well as any products such as vitamins, minerals, or other dietary supplements. You should bring this list with you each time you visit a doctor or if you are admitted to a hospital. It is also important information to carry with you in case of emergencies.

Brand names

  • Colprep®
  • Suprep®
  • Sutab®

This branded product is no longer on the market. Generic alternatives may be available.

Last Revised - 05/15/2021