Fluoxetine, which people may know by the brand name Prozac, is a type of antidepressant belonging to a group of medications called selective serotonin reuptake inhibitors (SSRIs). When stopping Prozac or another antidepressant, people may experience discontinuation symptoms.

Many people who stop or reduce their use of antidepressants may experience withdrawal symptoms, which doctors refer to as antidepressant discontinuation syndrome. In fact, some research suggests that up to 80% of people who abruptly stop antidepressants may develop discontinuation symptoms.

Symptoms that people commonly experience when stopping Prozac include irritability, nightmares, and vomiting. For this reason, a person who feels ready to discontinue the drug should discuss this with their doctor, who may recommend gradually lowering their dosage.

In this article, we discuss the symptoms of Prozac discontinuation, including how long they last. We also explain when to see a doctor.

A closeup of Prozac, or another antidepressant, medication.Share on Pinterest
MAURO FERMARIELLO/SCIENCE PHOTO LIBRARY/Getty Images

Fluoxetine, or Prozac, is a type of SSRI antidepressant. Prozac received approval for medical use in the United States in 1987. A 2020 study notes that during the last 20 years, doctors have commonly prescribed fluoxetine.

The Food and Drug Administration (FDA) has approved it to treat various conditions, including:

As with many other antidepressants, fluoxetine carries a black box warning. This warning alerts doctors and patients to the drug’s possible effects, such as suicidal thoughts and behaviors in adults less than 24 years old.

Research suggests that approximately 56% of people who attempt to come off antidepressants experience symptoms of medication withdrawal.

The reason for this is that suddenly stopping an antidepressant can cause a chemical imbalance in the brain, which can have physical and mental effects.

Antidepressants with a longer half-life, such as Prozac, are less likely to cause problems on discontinuation. The term half-life refers to how quickly the amount of a drug in the body reduces by half.

Prozac has an approximate half-life of 5 days, which is much longer than that of many other antidepressants.

A 2020 study notes that severe withdrawal symptoms are less common with fluoxetine than with other antidepressants. However, withdrawal from Prozac typically lasts longer than it does for drugs with a shorter half-life.

Withdrawal symptoms typically occur a few days after a person tapers their dosage. Common symptoms associated with reducing the dosage of Prozac include:

Typically, antidepressant discontinuation symptoms persist for up to 3 weeks. However, in some cases, symptoms may last for up to 6 weeks, and they can occasionally continue for up to 1 year.

As fluoxetine has a longer half-life than other antidepressants, it may take longer for a person to develop withdrawal symptoms. The symptoms may also last longer, although they do not tend to be severe.

Certain factors, such as the speed of a person’s metabolism, may also cause withdrawal symptoms to appear more quickly or gradually.

When a person decides that they are ready to discontinue Prozac, a doctor will likely recommend gradually reducing, or tapering, their dosage. Tapering usually lasts 4 weeks, but a doctor may suggest tapering the medication over 6–8 weeks to reduce the risk or severity of symptoms.

Due to the long half-life of Prozac, some people may not need to taper off and can simply stop taking it. However, a person should only do this under the guidance of a doctor.

According to Mind, the following self-care tips may also help a person coming off antidepressant medication:

  • telling family and friends about plans to come off antidepressants
  • having a healthy diet
  • getting adequate sleep
  • exercising regularly

A doctor may suggest therapy or counseling if the underlying condition remains after stopping the medication. This treatment approach may help a person understand, manage, and overcome the underlying cause of their mental health condition.

Learn more about how to stop antidepressants safely.

Antidepressants, such as Prozac, typically carry a black box warning, as they may worsen symptoms of depression or suicidal ideation and cause unusual changes in behavior in adults less than 24 years of age.

People taking Prozac and their loved ones or caregivers should watch for certain signs and symptoms. These may include:

  • restlessness
  • anxiety
  • irritability
  • insomnia
  • aggressiveness
  • a preoccupation with death or dying
  • getting affairs in order
  • feeling trapped or hopeless
  • talking about suicide
  • intense mood swings

If a person experiences these symptoms and behaviors, they should speak with a doctor.

Prozac may also interact with other medications or supplements and increase the risk of side effects. It is advisable to talk with a doctor before taking Prozac if currently taking:

  • medications that change heartbeat
  • other medications for depression
  • St. John’s wort

Additionally, Prozac may result in problems if a person:

  • has glaucoma
  • has epilepsy
  • has diabetes
  • is trying to become pregnant or is pregnant or nursing

Discontinuing an antidepressant can increase the risk of relapse, or the return of symptoms, for anxiety and depression. The long duration of Prozac withdrawal symptoms may also increase the likelihood of the person mistaking them for returning symptoms.

Abruptly stopping antidepressants can lead to rebound depression, in which symptoms return more intensely than before. It is important for doctors to determine the difference between withdrawal symptoms and returning symptoms, such as the return of depression.

A person should talk with their doctor if Prozac withdrawal symptoms are severe, concerning, disabling, or last longer than a few weeks. Additionally, it is important to seek help if a person experiences suicidal thoughts, self-harm, or any other unexpected or concerning symptoms.

A person should also seek help if the symptoms of the condition for which they were taking Prozac are redeveloping or worsening.

Fluoxetine, or Prozac, is an antidepressant that doctors commonly prescribe. When a person decides that they are ready to stop Prozac, they should discuss this with their doctor and follow their advice on discontinuation strategies.

Due to the long half-life of Prozac, it is less common for people to experience withdrawal symptoms than it is with other antidepressants. These symptoms may have a longer duration, but they are typically less severe. They may include dizziness, confusion, and headaches.

A doctor may consider tapering the dosage of Prozac to help avoid or reduce withdrawal. People can also try using self-care strategies, such as exercising, getting regular sleep, and having a healthy diet, to help minimize potential symptoms.