RESONIUM A Powder Ref.[10832] Active ingredients: Polystyrene sulfonate

Binding to other orally administered medications

Resonium A may bind to orally administered medications, which could decrease their gastrointestinal absorption and efficacy. Avoid co-administration of Resonium A with other orally administered medications. Administer Resonium A at least 3 hours before or 3 hours after other oral medications. For patients with gastroparesis, a 6-hour separation should be considered (see Sections 4.2 & 4.5).

Sorbitol

Gastrointestinal stenosis, intestinal ischemia and its complications (necrosis and perforation) may occur in patients treated with polystyrene sulfonate, especially in patients using sorbitol. Therefore concomitant use of Sorbitol with sodium polystyrene sulfonate is not recommended (see Section 4.5 Interactions and Section 4.8 Undesirable effects).

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

Because the resin may bind calcium and magnesium ions, deficiencies of these electrolytes may occur. Accordingly, patients should be monitored for all applicable electrolyte disturbances.

Other risks

In the event of clinically significant constipation, treatment should be discontinued until normal bowel movement has resumed. Magnesium-containing laxatives should not be used (see section 4.5 Interactions).

The patient should be positioned carefully when ingesting the resin, in order to avoid aspiration, which may lead to bronchopulmonary complications.

Children and neonates

In neonates, sodium polystyrene sulfonate should not be given by the oral route. In children and neonates particular care is needed with rectal administration as excessive dosage or inadequate dilution could result in impaction of the resin. Due to the risk of digestive haemorrhage or colonic necrosis, particular care should be observed in premature infants or low birth weight infants.

Patients at risk from an increase in sodium load

Care should be taken when administering to patients in whom an increase in sodium load may be detrimental (i.e. congestive heart failure, hypertension, renal damage or oedema). In such instances, adequate clinical and biochemical control is essential. The calcium form of the resin may have advantages in this situation.

Orally administered medications

Resonium A has the potential to bind to other orally administered medications. Binding of Resonium A to other oral medications could cause decrease in their gastrointestinal absorption and efficacy. Dosing separation of Resonium A from other orally administered medications is recommended (see sections 4.2 & 4.4).

Concomitant use not recommended

Sorbitol (oral or rectal): Concomitant use of Sorbitol with sodium polystyrene sulfonate is not recommended due to cases of intestinal necrosis and other serious gastrointestinal adverse reactions, which may be fatal (see Section 4.4 Special warnings and Section 4.8 Undesirable effects).

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. (See 4.4 Special warnings and special precautions for use).

Lithium: Possible decrease of lithium absorption.

Levothyroxine: Possible decrease of levothyroxine absorption.

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.

There are no specific warnings.

Metabolism and nutrition disorders

In accordance with its pharmacological actions, the resin may give rise to sodium retention, hypokalaemia and hypocalcaemia, and their related clinical manifestations (see Section 4.4 Special warnings and Section 4.9 Overdose).

Cases of hypomagnesaemia have been reported.

Gastrointestinal disorders

Gastric irritation, anorexia, nausea, vomiting, constipation and occasionally diarrhoea may occur. Faecal impaction following rectal administration particularly in children, and gastrointestinal concretions (bezoars) following oral administration have been reported. Gastrointestinal stenosis and intestinal obstruction have also been reported, possibly, due to co-existing pathology or inadequate dilution of the resin.

Gastrointestinal ischemia, ischemic colitis, gastro-intestinal tract ulceration or necrosis, which could lead to intestinal perforation have been reported which is sometimes fatal.

The majority of cases have been reported with concomitant use of Sorbitol (see Section 4.4 Special warnings and Section 4.5 Interactions).

Respiratory, thoracic and mediastinal disorders

Some cases of acute bronchitis and/or broncho-pneumonia associated with inhalation of particles of sodium polystyrene sulfonate have been described.

Reporting of suspected adverse reactions

Reporting suspected adverse reactions after authorisation of the medicinal product is important. It allows continued monitoring of the benefit/risk balance of the medicinal product. Healthcare professionals are asked to report any suspected adverse reactions via Yellow Card Scheme at: www.mhra.gov.uk/yellowcard or search for MHRA Yellow Card in the Google Play or Apple App Store.

There are no specific incompatibilities.