immunoglobulin: clinical use

Prescribing considerations

• Undertake an urgent exposure risk assessment and follow current UKHSA criteria.
• Prior rabies vaccination and immune status affect whether immunoglobulin is indicated.
• Clean the wound and infiltrate locally where anatomically possible; keep vaccine and immunoglobulin sites separate.
• Assess IgA deficiency, previous reactions, bleeding disorders, hydration and thrombotic risk.
• Record the product name and batch number.

Contraindications and cautions

• The selected product states that there are no contraindications because untreated rabies exposure is potentially life-threatening.
• Do not administer intravascularly.
• Use particular caution with IgA deficiency and anti-IgA antibodies, previous hypersensitivity, thrombotic risk factors and conditions precluding intramuscular injection.

Monitoring

• Ensure treatment for anaphylaxis or shock is immediately available.
• Monitor for hypersensitivity, hypotension and thromboembolic symptoms.
• Document the exposure assessment, administration sites, vaccine history, product and batch.
• Account for passive-antibody interference when interpreting serology or red-cell antibody tests.

Clinical pharmacology

A plasma-derived preparation composed mainly of IgG with a high concentration of rabies-neutralising antibodies. It supplies passive immunity and is subsequently catabolised through normal IgG pathways.

Formulation and product differences

• A clear or slightly opalescent, colourless to pale-yellow solution for injection in a single-use vial.
• Potency and fill volume vary between batches and are printed on the vial label.
• Contains a small quantity of IgA and excipients including sodium chloride, glycine and sodium acetate.
• Do not mix with other medicinal products or use cloudy solutions or those containing deposits.