sodium picosulfate/magnesium oxide/anhydrous citric acid


soe-dee-um pi-koe-sul-fate/mag-nee-zhum ox-side/an-hye-druss sit-ric as-id

Trade Name(s)

  • Prepopik

Ther. Class.

Pharm. Class.
osmotic laxatives
stimulant laxatives


Cleansing of the colon in preparation for colonoscopy.


 Sodium picosulfate– converted by colonic bacteria to BHPM, which directly stimulates colonic peristalsis.  Magnesium oxide and anhydrous citric acid– combine to form magnesium citrate, an osmotic laxative that causes water retention within the GI tract.

Therapeutic Effect(s):

With concurrent fluid ingestion produces watery diarrhea and colonic purging in preparation for colonoscopy.


Absorption: Minimal systemic absorption.

Distribution: Action is primarily local.

Metabolism and Excretion: Action is primarily local.

Half-life:  Sodium picosulfate– 7.4 hr.

TIME/ACTION PROFILE (onset of watery diarrhea)

POwithin hrunknownunknown


Contraindicated in:

  • Severely impaired renal function (CCr <30 mL/min);
  • GI obstruction/ileus/bowel perforation/toxic colitis or megacolon/gastric retention.

Use Cautiously in:

  • Renal impairment/concurrent medications affecting renal function (↑ risk of renal impairment);
  • Known risk factors for arrhythmias including prolonged QT interval, recent MI, unstable angina pectoris, CHF, or cardiomyopathy;
  • Known/suspected inflammatory bowel disease (may cause mucosal ulcerations);
  • Electrolyte abnormalities (correct prior to administration);
  • History of seizures or concurrent use of medications that ↓ seizure threshold (may ↑ risk of seizures);
  • Patients at risk for aspiration;
  • OB:  Use during pregnancy only if clearly needed;
  • Lactation: Use caution if breastfeeding;
  • Pedi:   Safe and effective use in children has not been established.

Adverse Reactions/Side Effects

CNS: SEIZURES, headache


GI: abdominal pain, abdominal distention, abdominal pain, nausea, vomiting


F and E: dehydration, fluid/electrolyte abnormalities

* CAPITALS indicate life-threatening.
Underline indicate most frequent.



  • Concurrent use of drugs affecting fluid and electrolyte status/renal function including ACE inhibitors, angiontensin receptor blockers, corticosteroids, NSAIDs, diuretics, and other  laxatives  may ↑ risk of dehydration, renal impairment, seizures, hypotension, and fluid/electrolyte abnormalities.
  • Concurrent use of medications that ↓ seizure threshold, including  tricyclic antidepressants  or concurrent  alcohol benzodiazepine  withdrawal (may ↑ risk of seizures).
  • Absorption of  oral medications  taken within 1 hr of start may be altered.
  • Prior/concurrent  anti-infectives  may ↓ efficacy.
  • Concurrent use of other  laxatives  (may ↑ risk of mucosal ulcerations).
  • Concurrent of use of  digoxin  (electrolyte abnormalities may ↑ risk of toxicity).
  • Concurrent use of drugs that may induce the syndrome if inappropriate secretion of antidiuretic hormone (SIADH) including antipsychotics, carbamazepine, tricyclic antidepressants, and  SSRIs  may ↑ risk of water retention and electrolyte abnormalities.
  • Magnesium in preparation chelates and prevents the absorption of chlorpromazine, digoxin, fluoroquinolones, penicillamine, and  tetracycline ; these should be given at least 2 hr before or 6 hr after.


Each dose should be followed by 3 8-ounce drinks of clear liquid.

PO (Adults):  Split dose method– One reconstituted packet during evening before colonoscopy, repeated during the morning prior to the colonoscopy;  Day-before method– One reconstituted packet during afternoon or early evening before colonoscopy, repeated 6 hr later during evening prior to the colonoscopy. Additional clear liquids are required.


Powder for oral use (requires reconstitution) (orange): 10 mg sodium picosulfate/3.5 g manesium oxide/12 g anhydrous citric acid per packet


  • Assess patient for abdominal distention, presence of bowel sounds, and usual pattern of bowel function.
  • Assess color, consistency, and amount of stool produced. Watery diarrhea to clear liquid should be defecated at the completion.
  • Monitor for significant vomiting or signs of dehydration (orthostatic hypotension) following medication. Consider post-colonoscopy lab tests (electrolytes, creatinine, BUN) and treat accordingly. May occur up to 7 days after colonoscopy.
  • Assess for seizures, especially in patients with a seizure disorder or patients taking medications that lower seizure threshold, withdrawing from alcohol or benzodiazepines, or with hyponatremia.
  • Monitor ECG pre-dose and post-colonoscopy in patients with increased risk of arrhythmias (history of prolonged QT interval, uncontrolled arrhythmias, recent MI, unstable angina, HF, cardiomyopathy).

Lab Test Considerations:

May cause ↓ serum potassium, sodium, chloride, calcium, eGFR, and ↑ serum magnesium and creatinine.

Potential Diagnoses


  • Correct fluid and electrolyte abnormalities prior to therapy.
  • Assess for difficulty swallowing or history of regurgitation or aspiration prior to administering.
  • PO Reconstitute powder right before use; do not prepare solution in advance. Fill the supplied dosing cup with cold water up to lower (5-oz) line on cup and pour in contents of 1 packet of Prepopik powder. Stir for 2–3 min. Reconstituted solution may become slightly warm as powder dissolves. There are 2 dosing regimens:
    •  Split Dose (Preferred Method):  Take dissolved first packet the night before colonoscopy followed by five 8-oz drinks (upper line of dosing cup) of clear liquid before bed. On day of colonoscopy, take dissolved second packet followed by at least 3 8-oz drinks of clear liquid before colonoscopy. Drinking clear liquids may continue until 2 hr of colonoscopy.
    •  Day-Before Dosing:  Take dissolved first packet in afternoon or early evening followed by five 8-oz drinks of clear liquid before next dose. Take dissolved second packet in the late evening followed by 3 8-oz drinks of clear liquid before bed. Drinking clear liquids may continue until 2 hr of colonoscopy.

Patient/Family Teaching

  • Instruct patient to consume only clear liquids (no solid food or milk) on the day before colonoscopy and up to 2 hr before time of the colonoscopy. Reconstitute powder as directed and follow dosing regimen.
  • Caution patient to hydrate adequately with clear liquids before, during, and after use of Prepopik. Clear liquids include water, clear broth, apple juice, white cranberry juice, white grape juice, gingerale, plain jello (not red or purple), and frozen juice bars (not purple or red). Do not eat solid foods or drink milk during therapy.
  • Advise patient to notify health care professional if severe bloating, distention, or abdominal pain occurs following first packet of Prepopik. Delay second packet administration until symptoms resolve.
  • Advise patient not to take any other laxatives during therapy.
  • Instruct patient to notify health care professional promptly if hives, rash, vomiting that prevents you from keeping down the additional prescribed amounts of clear liquids needed after taking medication, dizziness, urinating less than normal, or headache occur.
  • Advise patient to notify health care professional of all Rx or OTC medications, vitamins, or herbal products being taken and to consult with health care professional before taking other medications.
  • Advise female patient to notify health care professional if pregnancy is planned or suspected or if breastfeeding.

Evaluation/Desired Outcomes

Clean colon prior to colonoscopy.

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