eslicarbazepine acetate: clinical use

Prescribing considerations

• Confirm the focal-onset seizure indication and whether treatment is monotherapy or adjunctive therapy.
• Assess renal function; use is not recommended in severe renal impairment.
• Use cautiously in mild or moderate hepatic impairment. Use in severe hepatic impairment is not recommended because evidence is lacking.
• Review cardiac disease, conduction abnormalities and medicines that prolong the PR interval.
• Consider relevant HLA-associated severe skin-reaction risk in genetically susceptible populations.
• Review contraception because eslicarbazepine induces CYP3A4 and can reduce hormonal contraceptive exposure.

Contraindications and cautions

• Hypersensitivity to eslicarbazepine acetate, another carboxamide derivative such as carbamazepine or oxcarbazepine, or a formulation excipient.
• Second- or third-degree atrioventricular block.

Monitoring

• Renal function before treatment and when clinically indicated.
• Serum sodium during routine review and more closely in renal disease, symptoms of hyponatraemia or use of other sodium-lowering medicines.
• Rash, systemic hypersensitivity and mucosal symptoms, particularly early in treatment.
• Mood, suicidal thoughts or behaviour.
• Dizziness, somnolence, vision and coordination where these affect safety.
• Cardiac symptoms or conduction where risk factors are present.
• INR with warfarin and lipid response with interacting statins.

Clinical pharmacology

A prodrug extensively converted to active eslicarbazepine, which stabilises inactivated voltage-gated sodium channels. Metabolites are predominantly renally eliminated. Eslicarbazepine is a weak CYP3A4 and UGT inducer and inhibits CYP2C19.

Formulation and product differences

• The selected tablet is scored and can be divided into equal parts; it may also be crushed and mixed immediately with water or soft food.
• The oral suspension should be shaken thoroughly and measured with the supplied oral syringe.
• Comparative bioavailability data support switching between tablets and suspension when clinically arranged.
• The oral suspension contains methyl parahydroxybenzoate, which may cause delayed allergic reactions, and sulphites, which may rarely cause severe hypersensitivity or bronchospasm.

Oral suspension

Route: Oral

Strengths: 50 mg/mL

Tablet

Route: Oral

Strengths: 200 mg, 800 mg