sodium sulfate/potassium sulfate/magnesium sulfate


soe-dee-um sul-fate/poe-tass-ee-um sul-fate/mag-nee-zhum sul-fate

Trade Name(s)

  • Colprep Kit
  • Suprep Bowel Prep Kit

Ther. Class.

Pharm. Class.


Cleansing of the colon in preparation for colonoscopy.


Unabsorbed cations and anions in the GI tract cause osmotic laxative effect by causing water retention in 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: Not metabolized; primarily eliminated via fecal excretion.

Half-life: 8.5 hr.

TIME/ACTION PROFILE (onset of watery diarrhea)

POwithin hrunknownunknown


Contraindicated in:

  • Hypersensitivity;
  • 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, HF, 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);
  • Gout (may ↑ uric acid levels);
  • Patients at risk for aspiration;
  • OB:  Use during pregnancy only if clearly needed;
  • Lactation: Use caution if breast feeding;
  • Pedi:   Safety and effectiveness not established.

Adverse Reactions/Side Effects

CNS: SEIZURES, headache


Endo: hyperuricemia

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


F and E: hypercalcemia, dehydration

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



  • Concurrent use of drugs affecting fluid and electrolyte status/renal function, including ACE inhibitors, angiotensin 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).
  •  Oral medications  taken within 1 hr of start may not be properly absorbed.
  • Concurrent use of other  laxatives  may ↑ risk of mucosal ulcerations.
  • May ↑ risk of  digoxin  toxicity in the presence of electrolyte abnormalities.


PO (Adults): One bottle during evening before colonoscopy (10–12 hr before second dose), repeated during the morning prior to the colonoscopy (≥3.5 hr before colonoscopy). Additional clear liquids are required after each dose.


Powder for oral use (requires reconstitution) (lemon): 17.5 g sodium sulfate/3.13 g potassium sulfate/1.6 g magnesium sulfate per bottle


  • Assess for significant vomiting and signs of dehydration after administration of prep kit.

Lab Test Considerations:

Monitor electrolytes, serum creatinine, and BUN if signs of dehydration occur.

Potential Diagnoses


  • PO Dilute each of two 16 ounces of Bowel Prep Kit solution with an additional 1 quart of water. 3 quarts (approximately 2.8 L) taken orally prior to the colonoscopy is required for colon cleansing.  Day prior to colonoscopy:  Eat a light breakfast or only clear liquids. Avoid red and purple liquids, milk, and alcoholic beverages.  Early in evening prior to colonoscopy:  pour contents of one bottle of Bowel Prep Kit into mixing container provided. Fill the container to 16 ounce fill line with water; drink the entire amount. Drink 2 additional containers filled to 16-ounce line with water over next hour.  Day of colonoscopy:  Have only clear liquids until after colonoscopy. Avoid red and purple liquids, milk, and alcoholic beverages.  Morning of colonoscopy (10 to 12 hours after the evening dose):  pour contents of second bottle of Bowel Prep Kit into mixing container provided. Fill to 16–ounce fill line with water, and drink entire amount. Drink two additional containers filled to 16-ounce line with water over next hour. Complete all Bowel Prep Kit and required water at least two hrs prior to colonoscopy.

Patient/Family Teaching

  • Instruct patient in correct technique for preparing and taking prep kit. Solution must be diluted as directed; ingestion of undiluted solution may increase risk of nausea, vomiting, and dehydration.
  • Advise patient to hydrate adequately before, during, and after prep. Advise patient to expect watery diarrhea after ingesting prep kit.
  • Inform patients to avoid taking other oral medications within 1 hr of each dose of prep kit; they may not be absorbed.
  • Instruct patient to avoid taking other laxatives while taking prep kit.
  • Advise female patient to notify health care professional if pregnancy is planned or suspected or if breast feeding.

Evaluation/Desired Outcomes

Watery diarrhea and cleansing of colon prior to colonoscopy.

sodium sulfate/potassium sulfate/magnesium sulfate is a sample topic from the Davis's Drug Guide.

To view other topics, please or .

Anesthesia Central is an all-in-one web and mobile solution for treating patients before, during, and after surgery. This collection of drug, procedures and test information is derived from Davis’s Drug, MGH Clinical Anesthesia Procedures, Pocket Guide to Diagnostic Tests, and MEDLINE Journals. .