Fluoxetine Side Effects and Controversies

Prozac, Paxil and Zoloft anti-depressant tablets, close-up

Jonathan Nourok / The Image Bank / Getty Images

Prozac is the brand name of the drug fluoxetine, a selective serotonin reuptake inhibitor (SSRI). SSRIs are second-generation antidepressants, which means they are newer than first-generation medications such as monoamine oxidase inhibitors (MAOIs) or tricyclic antidepressants (TCAs). As serotonin is involved in the regulation of anxiety as well as mood, clinicians sometimes prescribe SSRIs for phobia treatment, particularly social phobia.

Serotonin Basics

Serotonin is a neurotransmitter, a chemical that carries signals between neurons in the brain. SSRIs, including fluoxetine, slow the rate at which the brain reabsorbs serotonin, allowing it to spend more time in the space between neurons, known as the synaptic gap. This, in turn, allows the serotonin to transmit additional signals to the neurons.

Taking Fluoxetine

Fluoxetine is available by prescription only and in a variety of strengths. Clinicians prescribe it for daily or weekly use. Although you may begin to feel better right away, fluoxetine often takes a while to work and need to be in your system over time. If you have questions or concerns, call your physician for instructions. Never attempt to adjust your dosage or medication schedule without professional guidance.

The Danger of Suicidality in Children and Young Adults

Fluoxetine is one of the only antidepressants approved for clinically depressed youths. However, there is some controversy surrounding its use. Speak to your doctor, or your child's doctor, about the risks and benefits of fluoxetine in order to make an informed decision.

In 2004, the U.S. Food and Drug Administration began requiring all SSRIs, including fluoxetine, to carry a "black box" warning that stresses the increased risk for suicidality in children and adolescents. A black-box warning is the most stringent warning a drug can carry before the FDA pulls it from the shelves.

In 2007, the FDA ordered a review, expanded the directive to include anyone 24 years old or younger and added warnings to the black box about the higher risk of suicidality during the first 1 to 2 months of treatment.

If you are having suicidal thoughts, contact the National Suicide Prevention Lifeline at 1-800-273-8255 for support and assistance from a trained counselor. If you or a loved one are in immediate danger, call 911.

For more mental health resources, see our National Helpline Database.

The review examined data from a group of more than 2,1000 children taking SSRI medications, about 4 percent experienced suicidal thoughts, including suicide attempts, but none of the children were successful at taking their own life. 

More recent reviews suggest that the benefits of antidepressant medications likely outweigh their potential risks to children and adolescents with major depression and anxiety disorders.

Drug Interactions

According to the U.S. National Library of Medicine, fluoxetine can interact with a long list of other medications. As a special precaution for fluoxetine, do not take it if you have taken any monoamine oxidase inhibitor (MAOI) within the past two weeks, and do not begin an MAOI within five weeks after discontinuing fluoxetine or any other SSRI.

Other medications that could interact with fluoxetine include:

  • A variety of mood disorder treatments
  • Seizure medications
  • NSAID pain relievers
  • Migraine treatments

Natural remedies such as St. John's wort also interact with fluoxetine and other SSRIs. Make sure your doctor is aware of all prescription, over-the-counter, and natural remedies you use. Always seek professional advice before taking anything new while taking fluoxetine. Avoid alcohol and sedatives.

Side Effects of Fluoxetine

Drowsiness or nervousness may occur, particularly when you first start taking it fluoxetine. If you're having side effects from your medication, contact your doctor immediately. Avoid driving and operating heavy machinery until you know how you react to the medication

Fluoxetine can cause a variety of side effects, including, but not limited to:

  • Nausea
  • Tremor
  • Sexual side effects
  • Excessive sweating
Was this page helpful?
0 Sources
Verywell Mind uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
  • Medline Plus: Fluoxetine (2014)
  • National Institute of Mental Health: Antidepressant Medications for Children and Adolescents - Information for Parents and Caregivers