FLUVO‌

Generic composition: Fluvoxamine Maleate

Introduction

Fluvoxamine is an antidepressant which functions pharmacologically as a selective serotonin reuptake inhibitor (SSRIs); belonging to the chemical series, the 2-aminoethyl oxime ethers of alkyl ketones. Fluvoxamine is a selective serotonin-reuptake inhibitor majorly used to treat obsessive-compulsive disorder.

Therapeutic Category

• Antidepressants ; Class: SSRIs

Dosage forms available

• FLUVO 50 mg
• FLUVO 100 mg

Mechanism of action

The exact mechanism of action of fluvoxamine has not been fully determined, but appears to be linked to its inhibition of CNS neuronal uptake of serotonin. Fluvoxamine blocks the reuptake of serotonin at the serotonin reuptake pump of the neuronal membrane, enhancing the actions of serotonin on 5HT1A autoreceptors. Studies have also demonstrated that fluvoxamine has virtually no affinity for α1– or α2-adrenergic, β-adrenergic, muscarinic, dopamine D2, histamine H1, GABA-benzodiazepine, opiate, 5-HT1, or 5-HT2 receptors, despite having an affinity for binding to σ1 receptors.

Pharmacokinetics

Well absorbed, oral bioavailability 53% and not significantly affected by food, half-life 9-28 hours, plasma protein binding is about 80%, metabolized in liver and excreted by urine.

Indications

• Obsessive-compulsive disorder (OCD)
• Depression
• Generalized anxiety disorder (GAD)
• Social Anxiety Disorder (SAD)
• Post-traumatic Stress Disorder (PTSD)

Dose

• Adult: Initial dose 50 mg orally once a day at bedtime, increased by 50 mg increments every 4 to 7 days, maximum 300mg/day.
• Pediatric: 25mg orally a day at bedtime, increased by 25mg every 4-7 day, maximum 200mg/day
• Dose reduction and slow titration recommended in hepatic impairment and elderly

Side effects

Possible side effect includes: anorexia, constipation, dry mouth, headache, nausea, nervousness, skin rash, somnolence, liver toxicity, mania, increase urination, seizures, sweating, tremors, drowsiness, dizziness, (sleep problems) insomnia, abnormal ejaculation, muscle pain, loss of appetite

 Interactions

• Smoking may decrease effectiveness of fluvoxamine
• Concurrent use with Tricyclic Antidepressants(TCAs) may increase plasma levels of fluvoxamine
• Decrease metabolism and may increase effects of some beta blockers (propranolol), some benzodiazepines, carbamazepine
• Increase risk of bleeding with NSAIDS, aspirin, clopidogrel, or warfarin
• Concentrations of thioridazine and its two active metabolites, mesoridazine and sulforidazine, increased threefold following co administration of fluvoxamine.
• Reduces the clearance of benzodiazepines metabolized by hepatic oxidation (e.g., alprazolam, diazepam, midazolam, triazolam, etc).
• Elevated serum levels of clozapine have been reported in patients taking fluvoxamine maleate and clozapine.

Precaution

• Pregnancy category C
• Gradual withdrawal recommended
• Patients with history of seizure

Contraindication

• Hypersensitivity to fluvoxamine or other SSRIs or any excipient
• Concurrent use of MAOIs (or within 14 days of discontinuing fluvoxamine)