Dose and Administration

1. Rectal: 0.5 - 1.0 gm/kg every 20 minutes PRN, have infant retain dose for 15-20 minutes.

Indication

1. Hyperkalaemia (as an adjunct to other therapeutic measures).

Contraindications and Precautions

1. Hypernatraemia
2. Congestive heart failure
3. Caution in neonates with hypokalaemia and hypocalcaemia.

Clinical Pharmacology

Sodium polystyrene sulphonate is a cation-exchange resin prepared in the sodium phase with an in vivo exchange capacity of approximately 1 mmol of potassium per gm. As the resin passes along the intestine or is retained in the colon, the sodium ions are partially released and are replaced by potassium ions. For the most part this action occurs in the large intestine which excretes potassium ions to a greater degree than does the small intestine. The resin is not totally selective: potassium and small amounts of other cations such as magnesium and calcium can be lost during treatment. Treatment is slow with effective lowering of serum potassium taking hours to days.

Possible Adverse Effects

1. Gastrointestinal disturbances (nausea, vomiting, constipation, diarrhoea).
2. Hypokalaemia
3. Hypocalcaemia
4. Other electrolyte disturbances.

Special Considerations

1. Sodium content 100 mg/gm.
2. Administration with sorbitol facilitates passage through GI tract, prevents constipation.
3. For severe hyperkalaemia (>7.5 mmol/L) consider emergency therapy such as IV glucose and insulin or IV sodium bicarbonate.
4. Monitor serum electrolytes for hypernatraemia, hypokalaemia, hypocalcaemia.