fluvoxamine (Luvox)

Fluvoxamine is a drug that is used for treating several psychiatric disorders. It is a member of the class of drugs called selective serotonin reuptake inhibitors (SSRIs), a class that also includes fluoxetine (Prozac), sertraline (Zoloft), and paroxetine (Paxil).

Selective serotonin reuptake inhibitors affect neurotransmitters, chemicals that nerves in the brain use to communicate with each other. Neurotransmitters are released by nerves, travel across the spaces between nerves and then attach to receptors on other nerves. Many experts believe that an imbalance in neurotransmitters is the cause of depression and other psychiatric disorders. Fluvoxamine works by inhibiting the uptake of serotonin, a neurotransmitter, from the spaces between nerve cells following its release. Therefore, there is more serotonin available in the spaces to attach to other nerves and stimulate them.

• Fluvoxamine is used for treating obsessive-compulsive disorder (OCD) and social anxiety disorder.
• Fluvoxamine also has been used in the treatment of major depression, management of obesity, bulimia, schizophrenia, and panic disorder.
• Fluvoxamine was approved by the FDA for the treatment of obsessive-compulsive disorder in December 1994.

Side effects of fluvoxamine include:

• Anxiety
• Nervousness
• Sweating
• Nausea
• Decreased appetite
• Constipation
• Diarrhea
• Dry mouth
• Somnolence (sleepiness)
• Dizziness
• Weight loss
• Indigestion
• Vomiting
• Stomach pain
• Palpitations
• Abnormal dreams
• Insomnia
• Sexual dysfunction

Fluvoxamine also may cause abnormal bleeding, seizures, and manic episodes. Withdrawal of fluvoxamine may result in withdrawal symptoms. The most common symptoms of withdrawal are dizziness, tiredness, tingling of the extremities, nausea, vivid dreams, irritability, and poor mood. Other symptoms include visual disturbances and headaches.

Withdrawal reactions have been reported after an average of 12 to 36 weeks of treatment, but after as few as 5 weeks. Although most authorities recommend discontinuing treatment by gradually reducing the dose, symptoms still may occur. Symptoms generally appear within a few days of discontinuing medication and persist for an average of 12 days (up to 21 days). They are relieved within 24 hours by re-administering the medication that was discontinued. Antidepressants may increase the risk of suicide in children and adolescents. There are concerns that antidepressants also may increase the risk of suicide in adults. Patients with major depression may experience worsening of depression or suicidal thoughts regardless of whether or not they are treated. Therefore, patients started on antidepressants should be closely observed for signs of worsening suicidal thinking or changes in behavior.

• The usual starting dose for adults is 50 mg daily given as a single dose at bedtime.
• The dose may be increased in 50 mg increments every 4-7 days to achieve the desired response.
• The maximum dose is 300 mg/day. Doses greater than 100 mg should be administered as a divided dose.
• When using extended release tablets the starting dose is 100 mg at bedtime and the maximum dose is 300 mg.
• Children (8 to 17 years old) should start with 25 mg daily given at bedtime, and the dose may be increased by 25 mg every 4-7 days up to a maximum of 200 mg/day (8-11 years old) or 300 mg/day (12-17 years old). Doses greater than 50 mg should be administered as a divided dose.

• All SSRIs, including fluvoxamine, should not be taken with any of the monoamine oxidase inhibitor (MAOI) class of antidepressants such as isocarboxazid (Marplan), phenelzine (Nardil), tranylcypromine (Parnate), and procarbazine (Matulane) other drugs that inhibit monoamine oxidase such as linezolid (Zyvox) and intravenous methylene blue. Such combinations may lead to confusion, high blood pressure, tremor, and increased activity. Fluvoxamine should not be administered within 14 days of discontinuing an MAO inhibitor, and MAO inhibitors should not be administered within 14 days of stopping fluvoxamine. Similar reactions occur if fluvoxamine is combined with other drugs, for example, tryptophan, St. John's wort, meperidine (Demerol), and tramadol (Ultram) that increase serotonin in the brain.
• Fluvoxamine can inhibit the elimination of clozapine (Clozaril), necessitating dosage reductions of clozapine.
• Fluvoxamine also may inhibit the elimination and increase the blood levels of theophylline (Theodur, Uniphyl), alprazolam (Xanax), and triazolam (Halcion) leading to side effects from these drugs.
• Fluvoxamine may increase the effect of warfarin (Coumadin, Jantoven), leading to excessive bleeding. Warfarin therapy should be monitored more frequently in patients who also are taking fluoxetine.
• Combining SSRIs with aspirin, nonsteroidal anti-inflammatory drugs or other drugs that affect bleeding may increase the likelihood of upper gastrointestinal bleeding. Fluvoxamine may increase blood levels of tizanidine (Zanaflex), thioridazine (Mellaril), alosetron (Lotronex), and pimozide (Orap), leading to increased side effects of these drugs.

• There are no adequate studies of fluvoxamine in pregnant women. Infants exposed to SSRIs in late pregnancy may have an increased risk for persistent pulmonary hypertension of the newborn (PPHN), which can be fatal.
• Fluvoxamine is excreted into breast milk. There are no adequate studies in lactating women.

What preparations of fluvoxamine are available?

• Tablets: 25, 50 and 100 mg.
• Tablets (extended release): 100 and 150 mg.

How should I keep fluvoxamine stored?

Tablets should be kept at room temperature, 15 C - 30 C (59 F - 86 F).