Home Blog

Uses and Side Effects of Prozac: A Comprehensive Overview

Uses and Side Effects of Prozac
Written by:

Rabia Khaliq

MSc in Applied Psychology

Dr. David Toomey



Medical Disclaimer
The medications listed on this website are provided for informational purposes only. Their inclusion does not guarantee that they will be prescribed to any individual, as treatment decisions are ultimately at the discretion of healthcare providers. This list is not exhaustive, and healthcare providers may prescribe other medications, including non-stimulant options, based on the patient’s unique health circumstances and needs. Read more

Prozac is the brand name of the drug Fluoxetine which belongs to the class of antidepressants called selective serotonin reuptake inhibitors (SSRIs). In 1988, Prozac made its debut in the United States, where it quickly rose to become among the most frequently prescribed antidepressants. Despite the availability of more modern medications like sertraline and citalopram, it is nevertheless widely used. Prozac is prescribed to treat a variety of ailments, including depression and anxiety disorders.

The usage of Prozac is linked to certain negative effects, though. So, in this article, we will cover all the basic information on this antidepressant, how it works, the side effects of Prozac, its uses, and precautions.

Get your online prescription from certified doctors after a complete evaluation of your symptoms through MEDvidi.

What Is Prozac?

Prozac is a prescription medication, a second-generation antidepressant classified as a selective serotonin reuptake inhibitor (SSRI). Although it was initially developed to treat depression, now it is frequently recommended to treat several other conditions. It helps to eliminate the symptoms of anxiety and obsessive-compulsive disorder by affecting specific chemical messengers (neurotransmitters) that interact between brain cells.

Fluoxetine HCL, a generic version of Prozac, is also offered. It is available as a delayed-release capsule, pills, capsule, and solution.

What Is Prozac Used For?

The Food and Drug Administration (FDA) approved Prozac in 1987 for the following conditions:

  • Major Depressive Disorder (MDD)
  • Panic Disorder
  • Eating disorders (Bulimia Nervosa)
  • Premenstrual Dysphoric Disorder (PMDD)
  • Treatment-Resistant Depression (TRD)
  • Obsessive-Compulsive Disorder (OCD)

Prozac is also commonly used off-label to treat the following conditions:

  • Borderline Personality Disorder (BPD)
  • Post-Traumatic Stress Disorder (PTSD)
  • Social Anxiety Disorder (SAD)
  • Premature ejaculation
  • Fibromyalgia
  • Migraine

What Does Prozac Feel Like When It Starts Working?

Prozac is an SSRI that decreases or eliminates depression symptoms by affecting the ability of neurons in the brain to absorb serotonin. Serotonin is a type of neurotransmitter that serves as a chemical messenger in the brain, setting up the “communication” between the brain cells. When the absorption of serotonin is blocked by Prozac, it boosts the communication between the brain cells, thereby helping to stabilize mood.

It is also known to stimulate neurons in the hippocampus, a region of the brain that aids in memory formation. Patients using Prozac may feel both physical and mental improvements, such as an improved mood, more energy, better sleep and eating patterns, and a resurgence of interest in previously loved hobbies.

How Long Does It Take for Prozac to Work?

It takes time for Prozac to modify serotonin levels in the brain as well as lessen depressive symptoms. While a lot of patients anticipate a quick improvement in their mental state, this medicine is a long-term drug that requires some time, 4-6 weeks in most cases, to reach its full effect.

Sometimes in as little as one to two weeks, Prozac starts to ease the physical signs of depression including erratic sleep, appetite, or activity levels.

Commonly Prescribed Dosage

The patient’s age, medical history, and the ailment being treated are critical factors considered for the optimal dosage. The standard oral dose for depression in adults is between 10-20 milligrams (mg) taken in the morning once a day. The dosage may increase if symptoms do not go away after a few weeks. The maintenance dose is between 20 and 60 mg per day, whereas the daily maximum dose is 80 mg. Prozac is also available as a 90 mg delayed-release oral capsule taken once a week by an adult for depression.

Note: Only your doctor can recommend the right dosage for your condition.

Prozac Side Effects

Despite the efficacy, Fluoxetine’s side effects can not be ignored. In addition to common and mild side effects, it may cause some serious side effects in a few cases.

Common Side Effects Serious Side Effects
  • Sexual dysfunction
  • Dryness of mouth
  • Nausea or vomiting
  • Headache
  • Nervousness
  • Diarrhea
  • A feeling of unease
  • Increased sweating
  • Changes in weight (gain or loss)
  • Sleeplessness
  • Lethargy
  • Indigestion
  • Influenza signs
  • Infection of the sinuses or a painful throat
  • Irregular heartbeat (QT prolongation)
  • Impaired motor, cognitive, and judgment skills
  • Excessive bleeding
  • Skin rashes or allergic reactions
  • Suicidal ideas and actions
  • Serotonin syndrome, a disorder that can be fatal
  • The onset of mania or hypomania
  • Vision issues (angle-closure glaucoma)
  • Seizures
  • Low blood salt levels
  • Issues controlling blood sugar

Experiencing side effects of your medication? Obtain a consultation from health professionals.

Black Box Warning

The most severe warning a medicine can have is a FDA black box warning. If there are any major or life-threatening dangers linked with the use of the drug, the government frequently demands pharmaceutical companies place a strong warning on the drug’s label and patient instruction sheets.

In October 2004, the FDA released a public warning for adolescents using antidepressants; two years later, the advisory was expanded to cover young adults up to the age of 24. In the first one to two months after beginning treatment with Prozac, there is a higher risk of suicidal thoughts and actions, according to the black box warning.

What is Prozac used for

Prozac Drug Interactions

Drug interactions could alter how well your medications are working or increase the possibility of major adverse effects. As fluoxetine remains in your system for several weeks after your last dosage, it has the potential to interact with a wide range of medications, and it should be disclosed to your doctor or pharmacist before taking any other prescription medications.

The following medications may result in severe interactions when used with Prozac:

  • Antiepileptic drugs like clopidogrel
  • NSAIDs like ibuprofen
  • Blood thinners like warfarin
  • Aspirin
  • MAO inhibitors (the majority of MAO inhibitors should also not be used for two weeks before and at least five weeks after switching to Prozac)

Experiencing side effects of your medication? Get the right consultation from health professionals.

Can Prozac Give Withdrawals?

When a person stops using the medicine, withdrawal symptoms could develop. These symptoms occur as a result of the quick change in serotonin levels that happen after stopping certain antidepressants. So, some people may have withdrawal symptoms after stopping Prozac. The onset, severity, and length of Fluoxetine/Prozac withdrawal symptoms can vary.

When someone stops taking fluoxetine or another SSRI, they could experience the following withdrawal symptoms:

  • A sense of detachment
  • “Brain zaps,” or feelings of an electric jolt to the skull
  • Depression
  • Anxiety
  • Difficulty focusing
  • Fatigue
  • Flu-like symptoms, such as body aches, or chills
  • Uncontrollable movements
  • Mood swings

Antidepressant withdrawal symptoms, according to doctors, are often self-limiting and pass within a few weeks.

Precautions For Using Prozac

Discussing the following issues with your doctor before starting Prozac will help them to determine whether this medication is the best choice for you.

  • If you have a medicine allergy or a reaction to any of the substances in capsules, tablets, or solutions, talk to your doctor.
  • Inform your doctor and pharmacist about any additional prescription drugs, over-the-counter remedies, and vitamins you are now taking or intend to use.
  • Inform your doctor about any dietary supplements and herbal remedies you are using, especially if they contain tryptophan or St. John’s wort.
  • Additionally, let your doctor know if you are receiving electroshock therapy or have low potassium, magnesium, or sodium levels in your blood.
  • Inform your doctor if you are expecting, especially if you are in the last few months of your pregnancy or if you are nursing a baby. Call your doctor right away if you get pregnant while taking fluoxetine. If fluoxetine is taken throughout the final months of pregnancy, it may have negative effects on the baby after birth.

Bottom Line

Prozac is a highly effective medication in the treatment of anxiety and depression, however the side effects of Prozac must be considered when prescribing it to patients. Even though not all of these side effects are likely to occur, if they do, medical treatment may be required. If you have any of the mentioned side effects, consult with your prescriber right away. For online consultation with certified doctors contact us at MEDvidi.com.

Show more
Written by:

Rabia Khaliq

MSc in Applied Psychology

Dr. David Toomey



Prioritize your mental well-being

Consult a healthcare professional online and receive a treatment plan tailored to your needs.

Recommended Articles

Join our newsletter

Sign up to receive mental health news and tips delivered right in your inbox every month.


Evidence Based

This article is based on scientific evidence, written by experts and fact checked by experts.

Our team of experts strive to be objective, unbiased, honest and to present both sides of the argument.

This article contains scientific references. The numbers
in the parentheses (1, 2, 3) are clickable links to peer-reviewed scientific papers.