fluvoxamine maleate: clinical use

Prescribing considerations

• Assess suicide risk and monitor clinical worsening, particularly early in treatment and after treatment changes.
• Review all medicines for serotonergic, bleeding-related and CYP-mediated interactions.
• Use caution with hepatic or renal impairment, older age, controlled epilepsy, diabetes, glaucoma, previous mania or hypomania, recent myocardial infarction and concurrent electroconvulsive therapy.
• Avoid abrupt discontinuation because withdrawal reactions are common and can occasionally be prolonged.
• Paediatric treatment under the selected licence is restricted to OCD in those over 8 years; it is not licensed for depression under 18.

Contraindications and cautions

• Hypersensitivity to fluvoxamine or an excipient.
• Concurrent tizanidine.
• Concurrent monoamine oxidase inhibitor treatment, subject to product-specific switching restrictions.
• Concurrent pimozide.

Monitoring

• Suicidal thoughts, behavioural change and clinical response.
• Mania, akathisia, seizures and serotonin toxicity.
• Bleeding where anticoagulants, antiplatelets or NSAIDs are used.
• Clinical effects or concentrations of medicines with a narrow therapeutic index affected by CYP inhibition.
• Liver symptoms or enzymes where clinically indicated; discontinue if a symptomatic hepatic enzyme rise occurs.
• Glycaemic control in people with diabetes and possible hyponatraemia in susceptible patients.

Clinical pharmacology

Fluvoxamine is an SSRI with extensive hepatic metabolism. It strongly inhibits CYP1A2 and CYP2C19 and inhibits CYP2C9, CYP2D6 and CYP3A4 to a lesser extent; its metabolites are not expected to contribute materially to pharmacological activity.

Formulation and product differences

• The selected product is a white to off-white, scored, film-coated tablet that can be divided into equal halves.
• It should be swallowed with water without chewing.
• The formulation is essentially sodium-free.

Tablet

Route: Oral

Strengths: 50 mg, 100 mg