Indications
Sodium Polystyrene Sulfonate is used to lower a high level of potassium in the blood (hyperkalaemia). High potassium is common in kidney disease and with some medicines, and can cause dangerous heart rhythm problems.
How It Works
It is a resin (an exchange powder) that is not absorbed into the body. In the gut, mainly the large bowel, it swaps sodium for potassium. The potassium stays bound to the resin and leaves the body in the stool, so blood potassium falls over several hours to days. It is not fast enough on its own for a life-threatening emergency.
Dosage and Administration
Dose and duration are set by a doctor based on blood potassium tests, as prescribed. The usual adult dose by mouth is 15 g one to four times a day, mixed with a small amount of water (not fruit juice, which contains potassium). It can also be given rectally as an enema by a nurse, usually 30 g, retained for several hours if possible. Do not mix with Sorbitol. Children’s doses depend on body weight and are given as prescribed.
Interactions
- It can bind other medicines in the gut; take other oral medicines at least 3 hours before or after it (6 hours if you have slow stomach emptying).
- Sorbitol given with it has been linked to serious bowel damage and should be avoided.
- Antacids or laxatives containing magnesium or aluminium may reduce its effect and can cause a metabolic problem (alkalosis).
- Low potassium caused by it can increase the toxic effects of Digoxin.
- It may reduce absorption of Lithium and Levothyroxine.
Contraindications
- Blood potassium below 5 mmol/L.
- Blocked or narrowed bowel, or reduced bowel movement after surgery.
- By mouth in newborn babies, and in babies with reduced gut movement.
- Allergy to polystyrene sulfonate resins.
Side Effects
Common effects include constipation, loss of appetite, nausea, vomiting and stomach irritation. It can cause low potassium, low calcium and low magnesium, and the extra sodium may cause fluid build-up, swelling or worsening heart failure or high blood pressure. Rarely, it can cause serious bowel damage (ulcers, bleeding or tissue death), especially in people with bowel problems or after surgery.
Get urgent medical help for severe stomach pain, severe constipation or bloating, blood in the stool or black stools, vomiting blood, muscle weakness or cramps, an irregular heartbeat, or sudden breathlessness or swelling.
Pregnancy and Lactation
It is not absorbed, so it is not expected to reach the baby, but it may reduce absorption of some nutrients. Use in pregnancy and breastfeeding when the doctor considers it necessary.
Precautions and Warnings
- Blood potassium, calcium, magnesium and sodium levels must be checked regularly.
- Avoid constipation; your doctor may give a suitable laxative that does not contain Sorbitol or magnesium.
- Use with caution in heart failure, high blood pressure, swelling or other conditions where extra sodium may be harmful.
- Sit upright while taking it by mouth to avoid breathing it in.
Overdose
Overdose can cause low potassium (weakness, muscle cramps, irregular heartbeat), low calcium and severe constipation or bowel blockage. Seek medical help; blood tests and treatment of the low salts are needed.
Therapeutic Class
Potassium-binding cation exchange resin.
Storage
Store below 30°C in a dry place, with the container tightly closed, out of the reach of children. Use a freshly prepared mixture and do not keep it for more than 24 hours.
Prepared by the Oshud Alo team from standard drug references. For information only; always follow your doctor's advice.