Fluvoxamine maleate

How it works

It selectively inhibits presynaptic reuptake of serotonin, increasing serotonergic neurotransmission in the central nervous system.

Prescribing in practice

• Fluvoxamine is a potent inhibitor of several cytochrome P450 enzymes (notably CYP1A2 and CYP2C19) and markedly raises levels of substrates such as theophylline, clozapine, tizanidine and agomelatine, so review interactions carefully and avoid contraindicated combinations.
• Do not combine with monoamine oxidase inhibitors and observe the required washout, and avoid other serotonergic agents where possible because of serotonin syndrome risk.
• Monitor for suicidal ideation early in treatment and in younger adults, and counsel on increased bleeding risk with antiplatelet or anticoagulant co-therapy.

Monitoring

Monitor mood and suicidality, response in obsessive-compulsive disorder, and for serotonergic, hyponatraemic or bleeding adverse effects, with vigilance for interacting drug levels.

Counselling the patient

• Tell any prescriber you take fluvoxamine before starting new medicines, as it can raise levels of many drugs.
• Report worsening mood or thoughts of self-harm, especially in the first weeks.
• Do not stop abruptly; the dose should be reduced gradually.

Evidence & guidelines

Fluvoxamine is an established SSRI with a recognised role in obsessive-compulsive disorder supported by regulatory approval and NICE OCD guidance.