Dosage Forms
Excipient information presented when available (limited, particularly for generics); consult specific product labeling. [DSC] = Discontinued product
Powder, Oral:
Kalexate: (454 g [DSC]) [sorbitol free; contains sodium 100 mg (4.1 mEq)/g]
Kayexalate: (453.6 g [DSC]) [contains sodium 100 mg (4.1 mEq)/g]
Kionex: (454 g [DSC]) [contains sodium 100 mg (4.1 mEq)/g]
Generic: (15 g, 453.6 g, 454 g)
Suspension, Oral:
Kionex: 15 g/60 mL (60 mL, 473 mL) [contains alcohol, usp, methylparaben, propylene glycol, propylparaben, saccharin sodium, sodium 1500 mg (65 mEq)/60 mL, sorbitol; raspberry flavor]
SPS: 15 g/60 mL (60 mL, 120 mL, 473 mL) [contains alcohol, usp, methylparaben, propylene glycol, propylparaben, saccharin sodium, sodium 1500 mg (65 mEq)/60 mL, sorbitol; cherry flavor]
Generic: 15 g/60 mL (60 mL, 480 mL, 500 mL)
Suspension, Rectal:
Generic: 30 g/120 mL (120 mL); 50 g/200 mL (200 mL)
Pharmacology
Mechanism of Action
Removes potassium by exchanging sodium ions for potassium ions in the intestine (especially the large intestine) before the resin is passed from the body; the practical exchange capacity is 1 mEq potassium per 1 g of resin in vivo, and in vitro capacity is 3.1 mEq of potassium per 1 g of resin, therefore, a wide range of exchange capacity exists such that close monitoring of serum electrolytes is necessary.
Pharmacokinetics/Pharmacodynamics
Absorption
None
Excretion
Completely feces (primarily as potassium polystyrene sulfonate)
Onset of Action
Hours to days
Use: Labeled Indications
Hyperkalemia: Treatment of hyperkalemia.
Limitations of use: Due to delayed onset of action, sodium polystyrene sulfonate should not be used an emergency treatment for life threatening hyperkalemia.
Contraindications
Hypersensitivity to sodium polystyrene sulfonate, polystyrene sulfonate resins or any component of the formulation; hypokalemia (excluding Kayexalate); obstructive bowel disease; neonates with reduced gut motility; oral administration in neonates; rectal administration in neonates (sorbitol-containing formulations only)
Dosage and Administration
Dosing: Adult
Hyperkalemia:
Oral: 15 g 1 to 4 times daily.
Rectal: 30 to 50 g every 6 hours.
Dosing: Geriatric
Refer to adult dosing.
Dosing: Pediatric
Hyperkalemia: Limited data available: Note: Typically not first-line; used when necessary to increase potassium excretion (Lehnhardt 2011). Due to delayed onset of action, sodium polystyrene sulfonate should not be used an emergency treatment for life-threatening hyperkalemia.
Weight-based dosing: Infants, Children, and Adolescents:
Oral, nasogastric: 1 g/kg/dose every 6 hours; maximum dose: 15 g/dose; Note: Oral route more effective than rectal and is preferred (Fuhrman 2017; Lehnhardt 2011)
Rectal: 1 g/kg/dose every 2 to 6 hours; maximum dose range: 30 to 50 g/dose; retain at least 15 to 60 minutes (Fuhrman 2017; Lehnhardt 2011); Note: Sorbitol-free preparations are preferred (Fuhrman 2017)
Exchange-ratio based dosing: Infants and small children: Oral, nasogastric, rectal: 1 mEq K+/g of sodium polystyrene sulfonate resin as the basis for calculation.
Pretreatment of formula or expressed breast milk; decrease potassium load for renal failure patients: Limited data available; various approaches reported: Infants and Children:
Infant/Enteral formula: 0.5 to 2.6 g/100 mL of formula (Cameron 2013; Thompson 2015) or 0.25 to 1g/mEq K+ content of formula (Fassinger 1998; Taylor 2015), adjust dose based on patient serum potassium trends. After addition of the resin, shake vigorously to mix, allow to sit under refrigeration for 30 to 60 minutes, then decant liquid for feed and leave precipitate at the bottom. The extent of potassium removal depends on the formula; in one trial, Similac PM 60/40 samples showed significant decreases at additive amounts of 0.25 to 1 g/mEq K+ content of formula versus Suplena which only showed significant reduction of K+ concentrations in the formula at 1 g/mEq K+ content of formula (Taylor 2015). Other electrolyte concentrations may also be decreased (eg, Ca, Mg, Cu, Zn) and significant increases in sodium concentrations of the formula were consistently reported; patients should be monitored closely.
Expressed breast milk: Usual dose: ~1 g/100 mL; adjust based on patient serum potassium trends; reported dose range: 0.4 to 1.5 g/100 mL of expressed breast milk. After addition of the resin, shake vigorously to mix, allow to sit under refrigeration for 60 minutes, then decant liquid for infant feed and leave precipitate at the bottom. In addition to decreasing the potassium load of the feed (subsequently patient's serum K) (Thompson 2013), other electrolyte concentrations may also be decreased (eg, Ca, Mg, Cu, Zn) and sodium concentrations (breast milk and serum) increased; patients should be monitored closely (Thompson 2013).
Reconstitution
Powder for suspension:
Oral or NG: For each 1 g of the powdered resin, add ~3 to 4 mL of water or syrup (amount of fluid usually ranges from 20 to 100 mL). Do not heat the solution to enhance dissolution of the powder as heating impairs the exchange resin properties.
Enema: Suspend dose in 100 mL of an aqueous vehicle (eg, water, sorbitol 25%, methylcellulose 1%, dextrose 10%).
Administration
Oral or NG: Administer orally or via NG tube with patient in an upright position at least 3 hours before or 3 hours after other medications (patients with gastroparesis may require a 6 hour separation). Do not mix in orange juice or in any fruit juice known to contain potassium. Shake the suspension well prior to administration. Chilling the oral mixture will increase palatability. Sodium polystyrene sulfonate suspension may also be added to the patient's food (with the exception of potassium-containing food such as bananas and orange juice).
Rectal: Administer cleansing enema first. Administer sodium polystyrene sulfonate as a warm emulsion (body temperature). During administration, the solution should be agitated gently. Retain the enema in the colon for at least 30 to 60 minutes and for several hours, if possible. Once retention time is complete, irrigate the colon with a nonsodium-containing solution to remove resin.
Dietary Considerations
Do not mix in orange juice or in any fruit juice known to contain potassium. Some products may contain sodium.
Storage
Store at 25°C (77°F); excursions permitted to 15°C to 30°C (59°F to 86°F). Store repackaged product in refrigerator and use within 14 days. Freshly prepared suspensions should be used within 24 hours. Do not heat resin suspension.
Drug Interactions
Aluminum Hydroxide: Sodium Polystyrene Sulfonate may enhance the adverse/toxic effect of Aluminum Hydroxide. More specifically, concomitant use of these agents may increase the risk for intestinal obstruction. Management: Monitor for signs/symptoms of intestinal obstruction with concomitant use of calcium polystyrene sulfonate and aluminum hydroxide. Adequate fluid intake, laxative use, alternative antacid agents, and/or limiting duration of therapy may help reduce risks. Consider therapy modification
Antacids: May enhance the adverse/toxic effect of Sodium Polystyrene Sulfonate. The combined use of these two agents may result in metabolic alkalosis and/or loss of efficacy of the exchange resin. Management: To minimize this interaction, consider: a)separating doses by 2 or more hours; b)rectal administration of the exchange resin; or c)alternatives to antacids. Monitor for metabolic alkalosis and attenuation of SPS effects. Avoid magnesium hydroxide. Exceptions: Sodium Bicarbonate. Consider therapy modification
Digoxin: Sodium Polystyrene Sulfonate may enhance the adverse/toxic effect of Digoxin. Monitor therapy
Laxatives (Magnesium Containing): May enhance the adverse/toxic effect of Sodium Polystyrene Sulfonate. More specifically, concomitant use of sodium polystyrene sulfonate with magnesium-containing laxatives may result in metabolic alkalosis or with sorbitol may result in intestinal necrosis. Management: Avoid concomitant use of sodium polystyrene sulfonate (rectal or oral) and magnesium-containing laxatives. Avoid combination
Lithium: Sodium Polystyrene Sulfonate may decrease the serum concentration of Lithium. Management: Consider separating administration of lithium from administration of oral sodium polystyrene sulfonate by at least 6 hours. Consider therapy modification
Meloxicam: May enhance the adverse/toxic effect of Sodium Polystyrene Sulfonate. More specifically, concomitant use of meloxicam oral suspension (which contains sorbitol) may increase the risk for intestinal necrosis. Avoid combination
Sorbitol: May enhance the adverse/toxic effect of Sodium Polystyrene Sulfonate. More specifically, concomitant use of these agents may increase the risk for intestinal necrosis. Avoid combination
Thyroid Products: Sodium Polystyrene Sulfonate may decrease the serum concentration of Thyroid Products. Management: To minimize risk of interaction, separate dosing of oral sodium polystyrene sulfonate and thyroid products (e.g., levothyroxine) or administer sodium polystyrene sulfonate rectally. Monitor for signs/symptoms of hypothyroidism with concomitant use (oral). Consider therapy modification
Adverse Reactions
Frequency not defined.
Endocrine & metabolic: Hypernatremia, hypocalcemia, hypokalemia, hypomagnesemia, sodium retention
Gastrointestinal: Anorexia, constipation, diarrhea, fecal impaction, nausea, vomiting
<1%, postmarketing, and/or case reports: Bezoar formation, gastrointestinal hemorrhage, gastrointestinal ulcer, intestinal necrosis, intestinal perforation, ischemic colitis
Warnings/Precautions
Concerns related to adverse effects:
- Aspiration: Acute bronchitis and bronchopneumonia caused by inhalation of sodium polystyrene sulfonate particles have been reported; patients with impaired gag reflex, altered level of consciousness or patients prone to regurgitation may be at increased risk. Administer with the patient in an upright position.
- Electrolyte disturbances: Severe hypokalemia may occur; frequent monitoring of serum potassium is recommended within each 24-hour period; ECG monitoring may be appropriate in select patients. Cation-exchange resins may also affect other cation concentrations, possibly resulting in decreased serum magnesium and calcium.
- Fecal impaction: Large oral doses may cause fecal impaction (especially in elderly); rectal administration has been associated with fecal impaction in children.
- Intestinal necrosis: Intestinal necrosis (including fatalities) and other serious gastrointestinal events (eg, bleeding, ischemic colitis, perforation) have been reported, especially when administered with sorbitol; concomitant administration of sorbitol is not recommended. Increased risk may be associated with a history of intestinal disease or surgery, hypovolemia, prematurity, and renal insufficiency or failure. Use only in patients who have normal bowel function. Avoid use in any postoperative patient at risk for constipation or impaction until normal bowel function resumes; discontinue use if constipation occurs.
Disease-related concerns:
- Cardiovascular disease: Use with caution in patients with severe heart failure and/or hypertension; sodium load may exacerbate condition.
- Edema: Use with caution in patients with edema; sodium load may exacerbate condition.
- Renal impairment: Use with caution in patients with renal impairment.
Concurrent drug therapy issues:
- Drug-drug interactions: Potentially significant interactions may exist, requiring dose or frequency adjustment, additional monitoring, and/or selection of alternative therapy. Consult drug interactions database for more detailed information.
Special populations:
- Elderly: Higher doses in elderly patients may result in fecal impaction.
- Pediatric: Oral administration in neonates and use in neonates with reduced gut motility (postoperatively or drug-induced) is contraindicated. Rectal administration of sorbitol-containing formulations in neonates is also contraindicated. Use with caution in premature or low-birth-weight infants. Use with caution in children when administering rectally; excessive dosage or inadequate dilution may result in fecal impaction.
Dosage form specific issues:
- Propylene glycol: Some dosage forms may contain propylene glycol; large amounts are potentially toxic and have been associated hyperosmolality, lactic acidosis, seizures, and respiratory depression; use caution (AAP 1997; Zar 2007).
Other warnings/precautions:
- Appropriate use: Effective lowering of serum potassium from sodium polystyrene sulfonate may take hours to days after administration; consider alternative measures (eg, dialysis) or concomitant therapy (eg, IV sodium bicarbonate) in situations where rapid correction of severe hyperkalemia is required.
- Enema vs oral administration: Enema will reduce the serum potassium faster than oral administration, but the oral route will result in a greater reduction over several hours.
Monitoring Parameters
Serum electrolytes (potassium, sodium, calcium, magnesium); ECG in select patients; signs/symptoms of fluid overload in patients sensitive to sodium intake (eg, heart failure, hypertension, edema).
Pregnancy
Pregnancy Risk Factor
C
Pregnancy Considerations
Animal reproduction studies have not been conducted. Sodium polystyrene sulfonate is not absorbed systemically following oral or rectal administration. Use during pregnancy is not expected to result in significant exposure to the fetus.
Patient Education
What is this drug used for?
- It is used to treat high potassium levels.
Frequently reported side effects of this drug
- Lack of appetite
- Vomiting
- Nausea
Other side effects of this drug: Talk with your doctor right away if you have any of these signs of:
- Electrolyte problems like mood changes, confusion, muscle pain or weakness, abnormal heartbeat, seizures, lack of appetite, or severe nausea or vomiting.
- Shortness of breath
- Excessive weight gain
- Severe headache
- Bowel problems like black, tarry, or bloody stools; fever; mucus in stools; vomiting; vomiting blood; severe abdominal pain; constipation; or diarrhea.
- Severe diarrhea
- Severe headache
- Shortness of breath
- Excessive weight gain
- Swelling of arms or legs
- Signs of a significant reaction like wheezing; chest tightness; fever; itching; bad cough; blue skin color; seizures; or swelling of face, lips, tongue, or throat.
Note: This is not a comprehensive list of all side effects. Talk to your doctor if you have questions.
Consumer Information Use and Disclaimer: This information should not be used to decide whether or not to take this medicine or any other medicine. Only the healthcare provider has the knowledge and training to decide which medicines are right for a specific patient. This information does not endorse any medicine as safe, effective, or approved for treating any patient or health condition. This is only a brief summary of general information about this medicine. It does NOT include all information about the possible uses, directions, warnings, precautions, interactions, adverse effects, or risks that may apply to this medicine. This information is not specific medical advice and does not replace information you receive from the healthcare provider. You must talk with the healthcare provider for complete information about the risks and benefits of using this medicine.
