fluvoxamine
Meaning of fluvoxamine: Alone among the SSRIs sold in the United States, it carries no approval for depression, its labeled uses being obsessive-compulsive and social anxiety disorder.
Definition of fluvoxamine
Fluvoxamine is an antidepressant of the selective serotonin reuptake inhibitor class, best known for treating obsessive-compulsive disorder. It works by blocking the reabsorption of serotonin, a chemical messenger involved in mood, back into the nerve cells that released it, so more remains available to act on neighboring cells. It is taken by mouth and sold under the brand name Luvox.
What is it used for?
Its established use is obsessive-compulsive disorder, a condition in which intrusive thoughts drive repetitive behaviors performed to relieve the distress those thoughts create. An extended release form is also approved for social anxiety disorder. In many other countries the same drug is approved for major depression, and it is prescribed for panic disorder and other anxiety conditions as well. The effect on compulsive symptoms builds gradually over a number of weeks rather than appearing at once, and the doses used against obsessive-compulsive symptoms tend to run higher than those used for low mood.
How does it compare with other SSRIs?
| Feature | Fluvoxamine | Most other SSRIs |
|---|---|---|
| Main labeled use in the United States | Obsessive-compulsive disorder | Depression, usually with further uses added |
| Effect on liver enzymes | Strong inhibition of two major ones | Varies, and generally narrower |
| Long lasting active breakdown product | None | Fluoxetine has one; the others largely do not |
The enzyme effect is the practical difference. Fluvoxamine strongly inhibits CYP1A2 and CYP2C19, two liver enzymes that clear a long list of other drugs, so blood levels of caffeine, theophylline, clozapine, olanzapine, tizanidine and certain sedatives rise when it is added, sometimes steeply. That makes it the member of the class most likely to interact with other medication, and interaction checking carries more weight with it than with most SSRIs. Because it leaves no long lasting active breakdown product behind, it also clears the body relatively quickly, so stopping it abruptly is more likely to produce dizziness, irritability and brief electric shock sensations while the system readjusts.
What effects does it commonly cause?
Nausea is the most frequent complaint at the start and usually settles. Drowsiness is more prominent with fluvoxamine than with several others in the class, which is why it is often taken in the evening. Headache, dry mouth, sweating and disturbed sleep also occur, and sexual difficulty is a common reason people discontinue any SSRI. A rare but serious side effect is serotonin syndrome, an excess of serotonin activity marked by agitation, fever, tremor and a racing heart, which becomes more likely when several serotonin raising drugs are combined. Close monitoring for worsening mood or suicidal thinking is standard early in treatment and after any dose change, particularly in children and young adults.
Also known as
Used in a sentence
Fluvoxamine was prescribed to help manage the patient's obsessive-compulsive disorder.
Good to know
Fluvoxamine acts on the same serotonin system as other SSRIs, but it is the one member of the class marketed in the United States without an approval for depression, its labeled uses there being obsessive-compulsive disorder and social anxiety disorder.