Read this Medication Guide before you start taking OsmoPrep. This information does not take the place of talking with your doctor about your medical condition or your treatment.

Who should not take OsmoPrep?

Do not take OsmoPrep if you:

• have had a kidney biopsy that shows you have kidney problems because of too much phosphate.
• have stomach or bowel (intestine) blockage.
• had stomach surgery involving stapling or bypass.
• have an opening in the wall of your intestine (bowel perforation).
• have a severely inflamed colon (toxic colitis).
• have a very dilated intestine (toxic megacolon).
• are allergic to sodium phosphate salts or any of the ingredients in OsmoPrep. See the end of this Medication Guide for a complete list of ingredients in OsmoPrep.

What should I tell my doctor before taking OsmoPrep?

Before you take OsmoPrep, tell your doctor about all of your medical conditions, including if you:

• have problems with serious loss of body fluid (dehydration) and changes in blood salts (electrolytes).
• have kidney problems.
• have heart problems.
• have a history of seizures.
• have had stomach surgery.
• have stomach or bowel problems.
• have ulcerative colitis.
• have problems with swallowing, gastric reflux, or if you inhale food or fluid into your lungs when eating or drinking (aspirate).
• are withdrawing from alcohol use.
• are withdrawing from the use of a type of medicine called a benzodiazepine.
• are on a low salt diet.
• are pregnant or plan to become pregnant. It is not known if OsmoPrep will harm your unborn baby. Talk to your doctor if you are pregnant or plan to become pregnant.
• are breastfeeding or plan to breastfeed. It is not known if OsmoPrep passes into your breast milk. You and your doctor should decide if you will take OsmoPrep while breastfeeding.

Tell your doctor about all the medicines you take,including prescription and over-the-counter medicines, vitamins, and herbal supplements.

OsmoPrep may affect how other medicines work. Do nottake medicines by mouth within 1 hour of starting each dose of OsmoPrep or 1 hour after you start taking each dose of OsmoPrep.

Especially tell your doctor if you take:

• water pills (diuretics).
• medicines for blood pressure or heart problems.
• medicines for kidney problems.
• medicines for pain, such as aspirin or a nonsteroidal anti-inflammatory drug (NSAID).
• medicine for seizures.
• a laxative for constipation. Do nottake other laxatives while taking OsmoPrep, especially a laxative or enema that contains sodium phosphate.
• medicine for depression or other mental health problem called a benzodiazepine.

Ask your doctor or pharmacist if you are not sure if you take any of the medicines listed above.

Know the medicines you take. Keep a list of your medicines to show your doctor or pharmacist when you get a new prescription.

How should I take OsmoPrep?

• Take OsmoPrep exactly as prescribed by your doctor.
• On the day before your colonoscopy, you can eat a light breakfast before 12:00 PM (noon). Examples of foods that you can eat include: clear liquids and plain yogurt. Do not eat any solid foods on the day before your colonoscopy.After your light breakfast, eat or drink only clear liquids until after your colonoscopy.
• It is important for you to drink plenty of clear liquids before, during, and after taking OsmoPrep. This may help prevent kidney damage.Examples of clear liquidsare:
  • water
  • clear soda
  • clear broth soups
  • gelatin (without added fruit or topping)
  • herbal tea, black tea or coffee
  • popsicles (without pieces of fruit or fruit pulp)
  • watered down (diluted) (from concentrate) clear fruit juices (without pulp) including apple juice or white grape juice
  • strained limeade or lemonade
• Eat or drink only clear liquidsafter 12:00 PM (noon) on the day before your colonoscopy until after your colonoscopy.
• Do not eat solid foodstarting on the day before your colonoscopy until after your colonoscopy.
• Do noteat or drink alcohol, milk, anything colored red or purple or any foods that have pulp.
• You must read, understand, and follow these instructions to take OsmoPrep the right way:
• On the evening before your colonoscopy,take a total of 20 OsmoPrep tablets, as follows:
• Step 1. Take 4 OsmoPrep tablets with 8 ounces of clear liquids.
• Step 2. Wait 15 minutes.
• Step 3. Take 4 more OsmoPrep tablets with 8 ounces of clear liquids.
• Step 4. Repeat Steps 2 and 3 above, three more times. Make sure you wait 15 minutes after each time.

On the day of your colonoscopy,take a total of 12 OsmoPrep tablets, starting about 3 to 5 hours before your colonoscopy, as follows:

1. Step 1. Take 4 OsmoPrep tablets with 8 ounces of clear liquids.
2. Step 2. Wait 15 minutes.
3. Step 3. Take 4 more OsmoPrep tablets with 8 ounces of clear liquids.
4. Step 4. Repeat Steps 2 and 3 one more time.

If you take too much OsmoPrep, call your doctor or get medical help right away.

What should I avoid while taking OsmoPrep?

• Do not take other laxatives or enemas made with sodium phosphate while taking OsmoPrep.
• Do not use OsmoPrep if you have already used it in the last 7 days.

What are the possible side effects of OsmoPrep?

OsmoPrep can cause serious side effects, including:

• See “What is the most important information I should know about OsmoPrep?”
• Changes in certain blood tests.Your doctor may do blood tests before and after you take OsmoPrep to check your levels of calcium, phosphate, potassium, and sodium in your blood. Tell your doctor if you have any symptoms of too much fluid loss, including:
  • vomiting
  • urinating less often than normal
  • dizziness
  • headache
• Abnormal heartbeat (arrhythmias).Tell your doctor if you have an abnormal or irregular heartbeat while taking OsmoPrep.
• Seizures or fainting (loss of consciousness).People who take a medicine that contains sodium phosphate, such as OsmoPrep, can have seizures or faint even if they have not had seizures before. Tell your doctor right away if you have a seizure or faint while taking OsmoPrep.
• Sores (ulcers) in the lining of the colon.Tell your doctor right away if you have severe stomach-area (abdomen) pain or rectal bleeding.
• Serious allergic reaction.Get emergency medical care right away if you have symptoms of a serious allergic reaction, including:
  • swelling of the face, lips, tongue or throat
  • dizziness or lightheadedness
  • problems breathing or wheezing
  • skin rash
  • throat tightness
  • raised red patches on your skin (hives)
  • fainting

The most common side effects of OsmoPrep are:

• bloating
• stomach (abdominal) pain
• nausea
• vomiting

Tell your doctor if you have any side effect that bothers you or that does not go away.

These are not all the possible side effects of OsmoPrep. For more information, ask your doctor or pharmacist.

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

How should I store OsmoPrep?

• Store OsmoPrep at room temperature between 68ºF to 77°F (20ºC to 25°C).
• Throw away any OsmoPrep that is not used.

Keep OsmoPrep and all medicines out of the reach of children.

General information about the safe and effective use of OsmoPrep.

Medicines are sometimes prescribed for purposes other than those listed in a Medication Guide. Do not use OsmoPrep for a condition for which it was not prescribed. Do not give OsmoPrep to other people, even if they are going to have the same procedure that you are. It may harm them. You can ask your doctor or pharmacist for information that is written for health professionals.