Fluvoxamine was developed in the mid‑1970s and introduced clinically in 1983, and became the first SSRI approved by the U.S. Food and Drug Administration (FDA) specifically for treating Obsessive‑Compulsive Disorder (OCD). It belongs to a class of drugs called Selective Serotonin Reuptake Inhibitors (SSRIs), which are thought to work by increasing levels of a brain chemical called Serotonin — helping to regulate mood and reduce compulsive behaviors.

BRAND NAMES

Fluvoxamine is available under several brand names globally. The most common brand names include Luvox and Luvox CR (controlled-release) in the United States, and various other names internationally such as Fluvoxin, Uvox, and Faverin.

MECHANISM OF ACTION

Fluvoxamine's primary mechanism of action is the potent and selective inhibition of serotonin reuptake in brain neurons, classifying it as a Selective Serotonin Reuptake Inhibitor (SSRI). It also acts as a potent agonist at the sigma-1 receptor (S1R), which contributes to its unique therapeutic profile.

PHARMACOKINETICS                  

Absorption

Fluvoxamine is almost completely absorbed when taken by mouth, and eating food does not meaningfully change how much of the drug gets absorbed. 

Distribution

Fluvoxamine is a lipophilic SSRI that distributes broadly throughout body tissues, reaching especially high concentrations in the brain and liver.

Metabolism

Fluvoxamine is extensively metabolized in the liver, primarily via the cytochrome P450 (CYP) enzyme system, to at least eleven metabolites, none of which are pharmacologically active.

Excretion

Fluvoxamine is primarily excreted in the urine, almost entirely in the form of inactive metabolites, with only a small percentage of the unchanged drug being eliminated.

PHARMACODYNAMICS

The primary pharmacodynamic action of fluvoxamine is as a potentand selective serotonin reuptake inhibitor (SSRI), which increases serotonin concentrations in the brain by blocking its reuptake into presynaptic neurons. Fluvoxamine also has a unique action as a strong agonist of the sigma-1 receptor. 

ADMINISTRATION

Fluvoxamine is an oral selective serotonin reuptake inhibitor(SSRI) mainly used for the treatment of obsessive-compulsive disorder (OCD). Itmust be administered according to a healthcare provider's specific instructions

DOSAGE AND STRENGTH

Fluvoxamine is marketed in two main forms: immediate‑release (IR) tablets — typically 25 mg, 50 mg, or 100 mg — and extended‑release (ER) capsules — commonly 100 mg or 150 mg. The appropriate dose depends on factors such as the patient’s age, the condition being treated (especially Obsessive‑Compulsive Disorder, OCD), and whether the IR or ER version is used. 

DRUG INTERACTIONS

Fluvoxamine has numerous significant drug interactions, primarily because it is a potent inhibitor of several liver enzymes (cytochrome P450isoenzymes, especially CYP1A2, CYP2C19, CYP2C9, and CYP3A4) responsible for drug metablism. This can lead to increased levels of other medications in the body, raising the risk of serious adverse effects like serotonin syndrome, bleeding complications, and excessive sedation. 

FOOD INTERACTIONS

Fluvoxamine can be taken with or without food, as food does not significantly affect its absorption. However, it does interact with certain types of food, beverages, and supplements, which should be avoided or limited due to potential adverse effects.

CONTRAINDICATIONS

Fluvoxamine should not be used in individuals who have previously shown hypersensitivity to the medication, or together with specific drugs that may cause dangerous and potentially life-threatening effects, including serotonin syndrome and cardiac arrhythmias.

SIDE EFFECTS

  • Nausea, vomiting, or diarrhea → Gastrointest upset 

  • Indigestion → Dyspepsia 

  • Change in taste → Altered taste 

  • Decreased appetite → Reduced appetite 

  • Sweating → Hyperhidrosis 

  • Difficulty falling asleep or staying asleep →Insomnia 

  • Anxiety or nervousness → Anxiety / Nervousness 

OVER DOSE

An overdose of fluvoxamine can lead to symptoms such as nausea, vomiting, dizziness, drowsiness, rapid heartbeat, low blood pressure, seizures, and, in severe cases, coma or serotonin syndrome (agitation, high temperature, tremor, sweating).

TOXICITY

Fluvoxamine toxicity primarily involves central nervous system and serotonergic effects. Symptoms can include dizziness, agitation, tremors, confusion, drowsiness, nausea, vomiting, rapid heartbeat, low blood pressure, and in severe cases serotonin syndrome, seizures, or coma. Toxicity risk increases when combined with other serotonergic drugs, MAO inhibitors, or substances that inhibit its metabolism.