HalfLytely and Bisacodyl

• It is used to clean out the GI (gastrointestinal) tract.

• Tell all of your health care providers that you take this medicine. This includes your doctors, nurses, pharmacists, and dentists.
• Do not use other laxatives or stool softeners unless told to do so by the doctor.
• If you are 65 or older, use HalfLytely and Bisacodyl with care. You could have more side effects.
• Tell your doctor if you are pregnant or plan on getting pregnant. You will need to talk about the benefits and risks of using this medicine while you are pregnant.
• Tell your doctor if you are breast-feeding. You will need to talk about any risks to your baby.

Use HalfLytely and Bisacodyl as ordered by your doctor. Read all information given to you. Follow all instructions closely.

Tablet:

• Swallow whole. Do not chew, break, or crush.
• Take with a full glass of water.
• Do not take antacids within 1 hour of this medicine.

Powder:

• Take HalfLytely and Bisacodyl as your doctor has told you. Follow all instructions you have been given closely. This includes when to take this medicine, foods and drinks to avoid before the exam, and when to stop eating and drinking before the exam. Talk with your doctor if you have any questions.
• Do not take other drugs within 1 hour of starting HalfLytely and Bisacodyl. Talk with your doctor about how to take your other drugs with this medicine.
• Mix with water as told before you take HalfLytely and Bisacodyl. Do not swallow the dry powder.
• Some products come with flavors that can be added to the solution. Only add flavors that come with the kit.
• Chill the solution to make it taste better.
• Shake well before use.
• Drink clear liquids before, during, and after taking this medicine. Do not drink any liquids that are purple or red.
• Works best if you drink each part fast.
• Do not eat solid food while taking HalfLytely and Bisacodyl (polyethylene glycol-electrolyte solution and bisacodyl).

What do I do if I miss a dose?

• Take a missed dose as soon as you think about it.
• If it is close to the time for your next dose, skip the missed dose and go back to your normal time.
• Do not take 2 doses at the same time or extra doses.
• Call your doctor if you are not able to finish this medicine before your exam.

All drugs may cause side effects. However, many people have no side effects or only have minor side effects. Call your doctor or get medical help if any of these side effects or any other side effects bother you or do not go away:

• Bloating.
• Feeling full.
• Belly pain.
• Upset stomach or throwing up.
• Stomach cramps.

These are not all of the side effects that may occur. If you have questions about side effects, call your doctor. Call your doctor for medical advice about side effects.

You may report side effects to the FDA at 1-800-FDA-1088. You may also report side effects at http://www.fda.gov/medwatch.

• Store powder at room temperature.
• Store tablets at room temperature.
• Store liquid in a refrigerator. Throw away any part not used after 2 days.
• Keep all drugs in a safe place. Keep all drugs out of the reach of children and pets.
• Check with your pharmacist about how to throw out unused drugs.

Serious Fluid and Serum Chemistry Abnormalities

Advise all patients to hydrate adequately before, during, and after the use of HalfLytely and Bisacodyl Tablet Bowel Prep Kit. If a patient develops significant vomiting or signs of dehydration after taking HalfLytely and Bisacodyl Tablet Bowel Prep Kit, consider performing post-colonoscopy lab tests (electrolytes, creatinine, and BUN). Fluid and electrolyte disturbances can lead to serious adverse events including cardiac arrhythmias, seizures and renal impairment.

Patients with electrolyte abnormalities should have them corrected before treatment with HalfLytely and Bisacodyl Tablet Bowel Prep Kit. In addition, use caution when prescribing HalfLytely and Bisacodyl Tablet Bowel Prep Kit for patients with conditions, or who are using medications, that increase the risk for fluid and electrolyte disturbances or may increase the risk of adverse events of seizure, arrhythmias, and renal impairment. [see Drug Interactions (7.1)]

Seizures

There have been reports of generalized tonic-clonic seizures with the use of large volume (4 liter) PEG-based colon preparation products in patients with no prior history of seizures. The seizure cases were associated with electrolyte abnormalities (e.g., hyponatremia, hypokalemia, hypocalcemia, and hypomagnesemia) and low serum osmolality. The neurologic abnormalities resolved with correction of fluid and electrolyte abnormalities.

Use caution when prescribing the HalfLytely and Bisacodyl Tablet Bowel Prep Kit for patients with a history of seizures and in patients at risk of seizure, such as patients taking medications that lower the seizure threshold (e.g., tricyclic antidepressants), patients withdrawing from alcohol or benzodiazepines, patients with known or suspected hyponatremia, or patients using concomitant medications (such as diuretics) that increase the risk of electrolyte abnormalities. Monitor baseline and post-colonoscopy laboratory tests (sodium, potassium, calcium, creatinine, and BUN) in these patients.

Renal Impairment

Patients with impaired water handling who experience severe vomiting should be closely monitored including measurement of electrolytes (sodium, potassium, calcium, BUN and creatinine). Use caution when prescribing HalfLytely and Bisacodyl Tablet Bowel Prep Kit for patients with impaired renal function or patients taking concomitant medications that may affect renal function (such as diuretics, angiotensin converting enzyme inhibitors, angiotensin receptor blockers, or non-steroidal anti-inflammatory drugs). Advise these patients of the importance of adequate hydration and consider performing baseline and post-colonoscopy laboratory tests (electrolytes, creatinine, and BUN) in these patients.

Cardiac Arrhythmias

There have been rare reports of serious arrhythmias associated with the use of ionic osmotic laxative products for bowel preparation. Use caution when prescribing HalfLytely and Bisacodyl Tablet Bowel Prep Kit for patients at increased risk of arrhythmias (e.g. patients with a history of prolonged QT, uncontrolled arrhythmias, recent myocardial infarction, unstable angina, congestive heart failure, or cardiomyopathy). Pre-dose and post-colonoscopy ECGs should be considered in patients at increased risk of serious cardiac arrhythmias.

Ischemic Colitis

There have been reports of ischemic colitis in patients with use of HalfLytely and 20 mg Bisacodyl Tablets Bowel Prep Kit and HalfLytely and 10 mg Bisacodyl Tablets Bowel Prep Kit. If patients develop severe abdominal pain or rectal bleeding, patients should be evaluated as soon as possible.

Patients with Significant Gastrointestinal Disease

If gastrointestinal obstruction or perforation is suspected, perform appropriate diagnostic studies to rule out these conditions before administering HalfLytely and Bisacodyl Tablet Bowel Prep Kit.

Use with caution in patients with severe active ulcerative colitis.

Aspiration

Use with caution in patients with impaired gag reflex and patients prone to regurgitation or aspiration. Such patients should be observed during administration of the HalfLytely and Bisacodyl Bowel Prep Kit solution.

HalfLytely and Bisacodyl Tablet Bowel Prep Kit consists of PEG-3350, an osmotic laxative and bisacodyl, a stimulant laxative. Each HalfLytely and Bisacodyl Tablet Bowel Prep Kit [Polyethylene glycol (PEG) 3350, sodium chloride, sodium bicarbonate and potassium chloride for oral solution and bisacodyl delayed-release tablet] consists of one 2 liter bottle of HalfLytely (PEG-3350, sodium chloride, sodium bicarbonate and potassium chloride for oral solution) powder for reconstitution and one 5 mg bisacodyl, delayed-release tablet.

• Bisacodyl delayed-release tablet: Each pink, round, enteric coated bisacodyl delayed-release tablet (stamped “BRA”) contains 5 mg of bisacodyl, USP (C22H19NO4) with a molecular weight of 361.40. Inactive ingredients include lactose (anhydrous) NF, microcrystalline cellulose NF, croscarmellose sodium NF, magnesium stearate NF, Eudragit L 30-55, polyethylene glycol 400, talc USP, gelatin, calcium sulfate (anhydrous) NF, confectioners sugar, kaolin USP, sucrose NF, Opalux pink, beeswax, and carnauba wax. The bisacodyl delayed-release tablet is administered orally prior to drinking the HalfLytely solution [see Dosage and Administration (2)].
• HalfLytely (PEG-3350, sodium chloride, sodium bicarbonate and potassium chloride for oral solution): A white powder for reconstitution containing 210 grams of PEG-3350, 2.86 grams of sodium bicarbonate, 5.6 grams of sodium chloride, 0.74 grams of potassium chloride and 1 gram of flavoring ingredient (if applicable). Flavor Packs are available in Cherry, Lemon-Lime, Orange and Pineapple. This preparation can be used without the addition of a Flavor Pack. When dissolved in water to a volume of 2 liters, the HalfLytely solution is isosmotic, clear, and colorless. The HalfLytely solution is administered orally after taking the one bisacodyl delayed-release tablet [see Dosage and Administration (2)].

Mechanism of Action

Polyethylene glycol (PEG), which is an osmotic agent, causes water to be retained within the gastrointestinal tract.

Bisacodyl is hydrolyzed by intestinal brush border enzymes and colonic bacteria to form an active metabolite [bis-(p-hydroxyphenyl) pyridyl-2 methane; (BHPM)] that acts directly on the colonic mucosa to produce colonic peristalsis.

Pharmacodynamics

The stimulant laxative effect of bisacodyl, together with the osmotic effect of the unabsorbed PEG when ingested with a large volume of water, produces watery diarrhea.

Pharmacokinetics

When taken orally, PEG 3350 is minimally absorbed.

Bisacodyl, which is a prodrug, is converted to its active metabolite BHPM by intestinal brush border enzymes and colonic bacteria. The pharmacokinetics of bisacodyl following oral administration of the bisacodyl tablet has not been adequately characterized.

Each HalfLytely and Bisacodyl Tablet Bowel Prep Kit contains:

One 5 mg bisacodyl delayed-release tablet: pink, round, enteric coated, stamped “BRA” in a blister pack.

One 2 liter bottle of HalfLytely (PEG-3350, sodium chloride, sodium bicarbonate and potassium chloride for oral solution) powder for reconstitution containing 210 grams of polyethylene glycol (PEG) 3350, 2.86 grams of sodium bicarbonate, 5.6 grams of sodium chloride, 0.74 grams of potassium chloride, and 1 gram of flavoring ingredient (if applicable). After adding 2 liters of water, the reconstituted HalfLytely solution (clear and colorless) contains 31.3 mmol/L of PEG-3350, 65 mmol/L of sodium, 53 mmol/L of chloride, 17 mmol/L of bicarbonate and 5 mmol/L of potassium.

Lemon-Lime HalfLytely and Bisacodyl Tablet Bowel Prep Kit contains 1 gram lemon-lime flavoring ingredient. HalfLytely and Bisacodyl Tablet Bowel Prep Kit with Flavor Packs contain 4 packs (1gram each Cherry, Lemon-Lime, Orange and Pineapple flavors).

Storage:

Store at 20-25°C (68-77°F). Excursions permitted between 15-30°C (59-86°F). The reconstituted HalfLytely solution, which may be refrigerated, should be used within 48 hours.

Lemon-Lime HalfLytely and Bisacodyl Tablet Bowel Prep Kit              NDC 52268-523-01

HalfLytely and Bisacodyl Tablet Bowel Prep Kit with Flavor Packs     NDC 52268-523-02