What Does Prozac Feel Like When It Starts Working?

Prozac first made its appearance in the United States in 1988, and it quickly became one of the most widely prescribed antidepressants in the country. Despite newer drugs having been released since its appearance, Prozac remains popular.

Prozac is a selective serotonin reuptake inhibitor (SSRI) that increases serotonin levels in the body. Serotonin is most commonly known for its role as a mood stabilizer, and increasing serotonin levels often improves depression and anxiety symptoms. When Prozac reaches its full effects, users typically experience better sleep, a greater appetite, and an improved mood. 

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What Is Prozac?

Prozac, a name brand for fluoxetine, is a prescription medication used to treat depression, some eating disorders, obsessive-compulsive disorder, and panic attacks.

Additionally, Prozac is used to relieve the symptoms of premenstrual dysphoric disorder, which can include irritability, mood swings, breast tenderness, and bloating.

While these are the primary conditions Prozac is used to treat, it is sometimes used to treat attention-deficit disorder (ADHD), alcoholism, sleep disorders, borderline personality disorder, mental illness, headaches, Tourette’s syndrome, posttraumatic stress disorder (PTSD), sexual problems, obesity, and phobias.

How Does Prozac Work?

Prozac is part of a class of medications called selective serotonin reuptake inhibitors (SSRIs), which increase the amount of serotonin in the brain. Serotonin is a neurotransmitter or a chemical messenger that sends signals between nerve cells.

Serotonin plays a large role in many actions of your body, including:

  • regulating anxiety
  • reducing depression
  • stimulating nausea
  • healing wounds
  • maintaining bone health

Serotonin is most commonly revered for its role in mood stabilization. When serotonin levels are normal, you feel calmer, happier, more focused, more emotionally stable, and less anxious.

However, when serotonin levels in the brain are low, conditions such as depression, sleep trouble, and anxiety can appear. By increasing serotonin levels, Prozac helps to treat these conditions. 

What Happens When You Start Taking Prozac?

Those who start taking Prozac, and experience a positive response, will notice a decrease in their anxiety symptoms which then improves all aspects of their life.

Some of the benefits people who take Prozac notice include:

  • improved sleep and appetite
  • feeling more relaxed and less anxious
  • having more energy
  • having a greater interest in life
  • improved focus

However, many people often notice side effects that appear before the benefits can be observed. These side effects can include:

  • blurred vision
  • dizziness
  • anxiety
  • diarrhea
  • nausea
  • fatigue
  • dry mouth
  • sexual problems
  • lightheadedness
  • heartburn
  • headaches
  • sweating
  • loss of appetite

Many people notice that these side effects lessen over time or become less bothersome.

What Does Prozac Feel Like When It Starts Working?

Within the first week or two of taking Prozac, you will likely notice that your energy, appetite, and sleep begin improving. Additionally, during this time, the side effects that first appeared when taking Prozac will start to ease up or disappear entirely.

Over the next few months, as Prozac continues to work, you may notice that other symptoms of depression or anxiety have also improved. For example, when Prozac starts working, you may notice that your mood has improved, or you may become more interested in your daily activities.

As Prozac continues to work, you may start to feel like yourself again.

How Long Does It Take for Prozac to Work?

Immediate effects of Prozac are often observed within 1-2 weeks of taking it. However, the full effects of Prozac are often not observed until someone has been on it for 6 to 8 weeks. Because Prozac takes time to show its full effects, it is important not to stop taking Prozac, even if you think it is not working.

How Do I Know If My Fluoxetine Is Working?

It can be an extensive process to try and find the best antidepressant for you, leaving some people wondering if their fluoxetine (Prozac) is working.

Some early signals that fluoxetine is working include improvements in sleep, energy, or appetite within the first 1-2 weeks of taking it. 

However, there are some things to watch out for to determine that Prozac is not working for you, including:

  • feeling better immediately, but it doesn’t last
  • not sleeping well
  • mood is still low after a few months
  • unpleasant side effects
  • depression worsens

If you think that Prozac is not working for you, it is crucial to discuss discontinuing Prozac with your doctor as immediately stopping it can cause withdrawal symptoms such as:

  • irritability
  • mood changes
  • dizziness
  • agitation
  • anxiety
  • numbness or tingling in the hands or feet
  • confusion
  • sweating
  • tiredness
  • headache
  • difficulty falling or staying asleep.

If you wish to stop taking Prozac, your doctor will likely decrease your dose gradually to avoid these symptoms.

How Can DrHouse Help You? 

For those interested in antidepressants, DrHouse can connect you with a board-certified doctor in just 15 minutes. Your doctor can provide a consultation evaluating your symptoms and write an online prescription for Prozac if needed.

You can also discuss how your Prozac prescription is working for you, including any improvements or declines in symptoms. If your prescription is not working in the expected way, your online doctor can discuss gradually weaning you from the medication to ensure that your symptoms do not drastically worsen.

Key Takeaways

Prozac, the name brand for fluoxetine, is an antidepressant medication that increases serotonin levels in the body. Serotonin plays a vital role in many body processes, but it is most commonly known for its role as a mood stabilizer.

Prozac is FDA approved to treat many disorders, some of which include depression, obsessive-compulsive disorder, and panic attacks. Within 1-2 weeks of taking Prozac, users often experience improvements in appetite, sleep, and energy, and the full effects of Prozac are often observed within 6 to 8 weeks.

If you are interested in starting Prozac, meeting with an online doctor allows you to receive a consultation where your doctor can determine if Prozac is a good fit for you. Once on Prozac, your online doctor can help you determine if this antidepressant is a good fit for you and if it is producing the desired results. 


Content on the DrHouse website is written by our medical content team and reviewed by qualified MDs, PhDs, NPs, and PharmDs. We follow strict content creation guidelines to ensure accurate medical information. However, this content is for informational purposes only and not a substitute for professional medical advice, diagnosis, or treatment. For more information read our medical disclaimer.

Always consult with your physician or other qualified health providers about medical concerns. Never disregard professional medical advice or delay seeking it based on what you read on this website.

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