How Prozac Works for Panic Disorder

Prozac is the world's most widely prescribed antidepressant; it has been used by more than 35 million people worldwide.
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If you have panic disorder, you will likely be treated with antidepressant medication. One popular antidepressant used to treat panic disorder and other conditions is Prozac (fluoxetine).

Understanding Prozac

Prozac is the trademark name of the drug fluoxetine, a medication belonging to a class of antidepressants known as selective serotonin reuptake inhibitors (SSRIs). SSRIs first became available in the United States in the 1980s and quickly came to be the most commonly prescribed type of antidepressant medication. Due to the effectiveness, safety, and limited side effects of SSRIs, their popularity continued to grow.

Being the first SSRI introduced in the U.S., Prozac is the most well-known and one of the most prescribed antidepressants.

Doctors initially prescribed Prozac to treat depression. However, research has shown that it can treat a variety of mental health and medical conditions. Currently, Prozac is used in the treatment of major depressive disorder, bipolar disorder, eating disorders, chronic pain, migraines, irritable bowel syndrome, obsessive-compulsive disorder, and anxiety disorders including panic disorder and agoraphobia.

How Prozac Treats Panic Disorder

Prozac stabilizes your levels of serotonin, a naturally-occurring chemical in the brain that's linked to how we regulate our moods. People with mood and anxiety disorders have an imbalance of serotonin. As an SSRI, Prozac works to influence serotonin by inhibiting its absorption in nerve cells in the brain.

Common Side Effects

Prozac has the potential for side effects, which often vary for different people. Some of the most common side effects include:

  • Anxiety
  • Blurred vision
  • Dizziness
  • Dry mouth
  • Fatigue
  • Headaches
  • Heartburn
  • Increased sweating
  • Lightheadedness
  • Nausea
  • Nervousness
  • Sexual side effects
  • Sleep disturbances
  • Yawning

Many people experience side effects that later subside or become less bothersome. Please note that these are only some of the side effects that can occur while taking Prozac. Consult your doctor if you experience any side effects that become unmanageable or don’t go away.

Your doctor will need to monitor your reaction to your medication, especially when initially starting with Prozac or when adjusting your dosage.

Rare Side Effects

As with any medication, there is the potential to experience an allergic reaction to Prozac. Contact your doctor immediately if you experience any of the following rare side effects:

  • Accelerated heart rate
  • Difficulty breathing or swallowing
  • Extreme nervousness and anxiety
  • Feelings of confusion
  • Fever
  • Joint pain
  • Rash or hives
  • Seizures
  • Strange bleeding or bruising
  • Suicidal thoughts or behaviors
  • Swelling of the face, mouth, or tongue
  • Vomiting

If you are having suicidal thoughts, contact the National Suicide Prevention Lifeline at 988 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.

How Quickly Prozac Works

Don’t expect Prozac to immediately make you feel better. Improvements are often noticed days to weeks after starting Prozac, but it can actually take up to several months before you experience the full effect.

Try to give your medication some time before determining whether or not it's helping you.

Stopping Prozac

Never abruptly stop taking your prescription. Although Prozac is long-acting and tends to taper itself, discontinuing it on your own may lead to withdrawal symptoms, such as increased anxiety and irritability, headaches, confusion, and lightheadedness. Additionally, your panic disorder symptoms can worsen if you suddenly stop taking your medication. Your dosage of Prozac can be gradually and safely reduced with your doctor's guidance.


There are several precautions with Prozac, including:

  • Black box warning: In 2007, the Food and Drug Administration (FDA) issued a black box warning for all SSRIs. The FDA cautioned that SSRI usage has the potential to increase thoughts and behaviors related to suicide. This issue was found to be particularly concerning for children, adolescents, and young adults who are taking SSRIs. Prescribing doctors must be especially observant of young people just beginning SSRI usage and monitor for signs of worsening mood or any suicidal thoughts.
  • Pregnancy/nursing: Prozac can be passed on to unborn babies during pregnancy or through breast milk when a baby is nursing. If you're pregnant or nursing, consult with your doctor about the possible risks of taking Prozac.
  • Alcohol: It is recommended that you avoid alcohol while taking Prozac, as it may increase the medication's toxicity or decrease its effectiveness.
  • Lightheadedness, dizziness, and drowsiness: Prozac can make you feel lightheaded, dizzy, and tired. It's important to be cautious while driving or performing any other duties that require your full alertness and concentration.
  • Older adults: If you're 65 or older, you may be at higher risk for some side effects of Prozac, so it needs to be used with greater caution in this group.
  • Drug interactions: You should be cautious when taking Prozac with other medications, as drug interactions can lead to serious issues. Keep your doctor up-to-date on your current medications, both prescription and over-the-counter, as well as nutritional supplements or herbs you take.

A Word From Verywell

The information provided here is simply an overview regarding the use of Prozac for panic disorder. This information does not cover all potential variables, including possible side effects, precautions, and contraindications. Always talk to your medical provider about any questions and concerns you may have about your prescription.

14 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.
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Additional Reading

By Katharina Star, PhD
Katharina Star, PhD, is an expert on anxiety and panic disorder. Dr. Star is a professional counselor, and she is trained in creative art therapies and mindfulness.