RESONIUM A

Posology The dosage recommendations detailed in this section are a guide only; the precise requirements should be decided on the basis of regular serum electrolyte determinations.

Adults, including the elderly:

Oral: The usual dose is 15g three or four times a day. Each dose should be given as a suspension in a small amount of water or, for greater palatability, in syrup (but not fruit juices which contain potassium), in the ratio of 3 to 4ml per gram of resin.

Administer Resonium A at least 3 hours before or 3 hours after other oral medications. 5).

Rectal:

This route should be reserved for the patient who is vomiting or who has upper gastrointestinal tract problems, including paralytic ileus. It may be used simultaneously with the oral route for more rapid initial results or in patients with gastroparesis, who have other orally administered medications that are administered within 6 hours of Resonium A.

The resin may be given rectally as a suspension of 30g resin in 150ml of water or 10% dextrose, as a daily retention enema. In the initial stages administration by this route as well as orally may help to achieve a more rapid lowering of the serum potassium level.

The enema should if possible be retained for at least nine hours following which the colon should be irrigated to remove the resin. If both routes are used initially it is probably unnecessary to continue rectal administration once the oral resin has reached the rectum.

Paediatric population Oral:

In smaller children and infants correspondingly smaller doses should be employed by using as a guide a rate of 1mEq of potassium per gram of resin as the basis for calculation. An appropriate initial dose is 1g/kg body weight daily in divided doses, in acute hyperkalaemia.

5g/kg of body weight daily in divided doses for maintenance therapy. The resin is given orally, preferably with a drink (not a fruit squash because of the high potassium content) or a little jam or honey.

Rectal:

When refused by mouth it should be given rectally, using a dose at least as great as that which would have been given orally, diluted in the same ratio as described for adults. Following retention of the enema, the colon should be irrigated to ensure adequate removal of the resin.

). To be used with caution • Cation-donating agents: may reduce the potassium binding effectiveness of Resonium A. • Non-absorbable cation-donating antacids and laxatives: There have been reports of systemic alkalosis following concurrent administration of cation-exchange resins and non-absorbable cation-donating antacids and laxatives such as magnesium hydroxide and aluminium carbonate.

• Aluminium hydroxide: Intestinal obstruction due to concretions of aluminium hydroxide has been reported when aluminium hydroxide has been combined with the resin. • Digitalis-like drugs: The toxic effects of digitalis on the heart, especially various ventricular arrhythmias and A-V nodal dissociation, are likely to be exaggerated if hypokalaemia is allowed to develop.

4 Special warnings and special precautions for use). • Lithium: Possible decrease of lithium absorption. 6 Fertility, pregnancy and lactation No data are available regarding the use of polystyrene sulfonate resins in pregnancy and lactation.

The administration of Resonium A in pregnancy and during breast feeding therefore is not advised unless, in the opinion of the physician, the potential benefits outweigh any potential risks. 7 Effects on ability to drive and use machines There are no specific warnings.

4 Special warnings and Section

Binding to other orally administered medications:

Calcium Resonium may bind to orally administered medications, which could decrease their gastrointestinal absorption and efficacy. Avoid co-administration of Calcium Resonium with other orally administered medications. Administer Calcium Resonium at least 3 hours before or 3 hours after other oral medications.

5).

Gastrointestinal stenosis and ischaemia:

Gastrointestinal stenosis, intestinal ischemia and its complications (necrosis and perforation), some of them fatal, were reported in patients treated with polystyrene sulfonate alone or in combination with sorbitol. 5). Patients should be advised to seek prompt medical advice in case of newly developed severe abdominal pain, nausea and vomiting, stomach distension and rectal bleeding.

Lesions seen in polystyrene sulfonate-induced gastrointestinal damage may overlap with those seen in inflammatory bowel disease, ischemic colitis, infectious colitis, and microscopic colitis.

Severe gastrointestinal disorders:

Due to the risk of severe gastrointestinal disorders (such as bowel obstruction, ischaemia, necrosis or perforation) the use of polystyrene sulfonate is not recommended in patients with compromised gastrointestinal motility (including immediate post-surgery or drug-induced).

Hypokalaemia:

The possibility of severe potassium depletion should be considered and adequate clinical and biochemical control is essential during treatment, especially in patients on digitalis. Administration of the resin should be stopped when the serum potassium falls to 5mmol/litre.

Other electrolyte disturbances:

1 • In patients with plasma potassium levels below 5mmol/litre. • History of hypersensitivity to polystyrene sulfonate resins. • Obstructive bowel disease. • Resonium A should not be administered orally to neonates and is contraindicated in neonates with reduced gut motility (post-operatively or drug-induced).