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URL of this page: https://medlineplus.gov/druginfo/meds/a613020.html

Sodium Picosulfate, Magnesium Oxide, and Anhydrous Citric Acid

pronounced as (soe' dee um) (pi' koe sul' fate) (mag nee' zee um) (ox' ide)

Why is this medication prescribed?

Sodium picosulfate, magnesium oxide, and anhydrous citric acid is used in adults and children 9 years of age and older 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) so that the doctor will have a clear view of the walls of the colon. Sodium picosulfate is in a class of medications called stimulant laxatives. Magnesium oxide and anhydrous citric acid combine to form a medication called magnesium citrate. Magnesium citrate is in a class of medications called osmotic laxatives. These medications work by causing watery diarrhea so that the stool can be emptied from the colon.

How should this medicine be used?

Sodium picosulfate, magnesium oxide, and anhydrous citric acid combination comes as a powder (Prepopik®) to mix with water and as a solution (liquid) (Clenpiq®) to take by mouth. It is generally taken as two doses in preparation for a colonoscopy. The first dose is usually taken the night before the colonoscopy and the second dose taken the morning of the procedure. The medication may also be taken as two doses on the day before the colonoscopy, with the first dose taken the late afternoon or early evening before the colonoscopy and the second dose taken 6 hours later. 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 sodium picosulfate, magnesium oxide, and anhydrous citric acid combination exactly as directed. Do not take more or less of it or take it more often 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.

If you are taking the powder (Prepopik®), you will need to mix the medication powder with cold water right before you take it. If you swallow the powder 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, fill the dosing cup that was provided with the medication with cold water up to the lower line (5 ounces, 150 mL) that is marked on the cup. Pour in the contents of one packet of sodium picosulfate, magnesium oxide, and anhydrous citric acid powder and stir for 2 to 3 minutes to dissolve the powder. The mixture may become slightly warm as the powder dissolves. Drink the entire mixture right away. Mix the medication with water only when you are ready to take it; do not prepare the mixture in advance.

If you are taking the solution (Clenpiq®), drink the entire contents of one bottle of sodium picosulfate, magnesium oxide, and anhydrous citric acid solution directly from the bottle for each dose you are to take. Sodium picosulfate, magnesium oxide, and anhydrous citric acid solution comes ready to drink and should not be mixed with a liquid before use.

If you are taking the medication the night before and the morning of your colonoscopy, you will take your first dose between 5:00 to 9:00 p.m. on the night before your colonoscopy. After you take this dose, you will need to drink five 8-ounce (240 mL) drinks of clear liquid within the next 5 hours before you go to bed. You will take your second dose the next morning, about 5 hours before your colonoscopy is scheduled. After you take the second dose, you will need to drink three 8-ounce drinks of clear liquid within the next 5 hours, but you should finish all the drinks at least 2 hours before your colonoscopy.

If you are taking both doses of the medication the day before your colonoscopy, you will take your first dose between 4:00-6:00 p.m. on the evening before your colonoscopy. After you take this dose, you will need to drink five 8-ounce drinks of clear liquid within 5 hours. You will take your next dose 6 hours later, between 10:00 p.m. to 12:00 a.m. After you take the second dose, you will need to drink three 8-ounce drinks of clear liquid within 5 hours.

It is very important that you drink the required amounts of clear liquid during your treatment to replace the fluid that you will lose as your colon is emptied. You can use the dosing cup provided with your medication to measure your 8-ounce portions of liquid by filling the cup to the top line. You may find it easier to drink the full amount of liquid if you choose a variety of different clear liquid drinks.

You will have many bowel movements during your treatment with sodium picosulfate, magnesium oxide, and anhydrous citric acid combination. 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.

If you experience severe bloating or stomach pain after you take the first dose of this medication, wait until these symptoms go away before you take the second dose.

Your doctor or pharmacist will give you the manufacturer's patient information sheet (Medication Guide) when you begin treatment with sodium picosulfate, magnesium oxide, and anhydrous citric acid. 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 sodium picosulfate, magnesium oxide, and anhydrous citric acid,

  • tell your doctor and pharmacist if you are allergic to sodium picosulfate, magnesium oxide, or anhydrous citric acid, any other medications, or any of the ingredients in sodium picosulfate, magnesium oxide, and anhydrous citric acid powder or solution. 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. Be sure to mention any of the following: alprazolam (Xanax); amiodarone (Cordarone, Pacerone); amitriptyline; angiotensin converting enzyme inhibitors (ACEIs) such as benazepril (Lotensin, in Lotrel), captopril , enalapril (Epanid, Vasotec, in Vaseretic), fosinopril, lisinopril (Prinivil, Qbrelis, Zestril, in Zestoretic), moexipril, perindopril (Aceon, in Prestalia), quinapril (Accupril, in Accuretic and Quinaretic), ramipril (Altace), or trandolapril (in Tarka); angiotensin receptor blockers (ARBs) such as candesartan (Atacand), eprosartan (Teveten), irbesartan (Avapro, in Avalide), losartan (Cozaar, in Hyzaar), olmesartan (Benicar, in Azor and Tribenzor), telmisartan (Micardis, in Micardis HCT and Twynsta), or valsartan (Diovan, in Byvalson, Diovan HCT, Entresto, Exforge, and Exforge HCT); aspirin and other nonsteroidal anti-inflammatory drugs (NSAIDs) such as ibuprofen (Advil, Motrin, others) and naproxen (Aleve, Naprosyn, others); desipramine (Norpramin); diazepam (Diastat, Valium); disopyramide (Norpace); diuretics (water pills); dofetilide (Tikosyn); erythromycin (E.E.S., Erythrocin); estazolam; flurazepam; lorazepam (Ativan); medications for seizures; midazolam (Versed); moxifloxacin (Avelox); pimozide (Orap); quinidine (Quinidex, in Nuedexta); sotalol (Betapace, Betapace AF, Sorine); thioridazine; or triazolam (Halcion). Also tell your doctor if you are taking or have recently taken antibiotics. Your doctor may need to change the doses of your medications or monitor you carefully for side effects. Many other medications may also interact with sodium picosulfate, magnesium oxide, and anhydrous citric acid, so be sure to tell your doctor about all the medications you are taking, even those that do not appear on this list.
  • do not take any other laxatives during your treatment with sodium picosulfate, magnesium oxide, and anhydrous citric acid.
  • if you take any medications by mouth, take them at least 1 hour before you start taking sodium picosulfate, magnesium oxide, and anhydrous citric acid. If you are taking any of the following medications, take them 2 hours before you start taking sodium picosulfate, magnesium oxide, and anhydrous citric acid or 6 hours after you finish your treatment with this medication: digoxin (Lanoxin); chlorpromazine; fluoroquinolone antibiotics such as ciprofloxacin (Cipro), delafloxacin (Bexdela), gemifloxacin (Factive), levofloxacin, moxifloxacin (Avelox), and ofloxacin; iron supplements; penicillamine (Cuprimine, Depen); and tetracycline.
  • 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), any condition that stops food and fluid from being emptied from the stomach normally, or kidney disease. Your doctor may tell you not to take sodium picosulfate, magnesium oxide, and anhydrous citric acid.
  • tell your doctor if you have been drinking large amounts of alcohol or taking medications for anxiety or seizures and 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), seizures, a low level of sodium 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, or gastric reflux (condition in which backward flow of acid from the stomach causes heartburn and possible injury to the esophagus).
  • 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 sodium picosulfate, magnesium oxide, and anhydrous citric acid. 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?

Sodium picosulfate, magnesium oxide, and anhydrous citric acid may cause side effects. Tell your doctor if any of these symptoms are severe or do not go away:

  • nausea
  • stomach pain, cramps, or fullness
  • bloating
  • headache

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

  • vomiting, especially if you can't keep down the fluids that you need for your treatment
  • dizziness
  • fainting
  • shakiness, sweating, hunger, moodiness, or anxiety, especially in children
  • changes in heart rate and blood pressure that may happen up to 7 days after the procedure
  • deceased urination
  • stool that is bloody or black and tarry
  • bleeding from rectum
  • seizures
  • irregular heartbeat
  • rash
  • hives

Sodium picosulfate, magnesium oxide, and anhydrous citric acid may cause other side effects. Call your doctor if you have any unusual problems while you are 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).

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.

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

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 sodium picosulfate, magnesium oxide, and anhydrous citric acid.

Do not let anyone else take your medication.

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

  • Clenpiq®
  • Prepopik®
Last Revised - 11/15/2019