Fluoxetine: How Prozac Works and What It Treats

Author:

Jemma Strain

B.S. Psychology

Editor:

Emma Loker

B.S

We all go through tough times, but if you’ve been dealing with a mental health condition, you may be wondering if antidepressants are the right choice for helping you cope. If this is the case, you’ve probably come across the name “Prozac.”

Prozac is a brand name for an antidepressant called fluoxetine. But what is fluoxetine? Fluoxetine is a selective serotonin reuptake inhibitor (SSRI), often making it the “go-to” medication for managing conditions like depression and panic disorders. This is because, in comparison to some antidepressants, fluoxetine typically has fewer side effects. But this doesn’t mean it works for everyone.

Here’s the thing few people will tell you about mental health conditions: They can be a hugely invisible struggle. The smallest tasks might feel overwhelming, you might think you can’t share what you’re going through, and you may even believe that treatment won’t work.

Mission Connection can see the weight of what you’re carrying – and we can help. We can highlight the pros of fluoxetine against the cons, and discuss the option of therapy for your needs. This article can also help by discussing:

What fluoxetine is and how it works for certain mental health conditions
How long it takes for Prozac to work
The common side effects of fluoxetine
How to stop Prozac safely
Different questions to ask your healthcare provider about fluoxetine
Where to find professional support for coping with mental health conditions and medication

What Is Fluoxetine?: How Prozac Works

Fluoxetine, sold under the brand name “Prozac,” is a Food and Drug Administration (FDA) approved medication for treating a variety of mental health conditions, including depression.¹

Fluoxetine is a selective serotonin reuptake inhibitor (SSRI), which means it increases the amount of serotonin in the brain. Serotonin is often called the “feel-good” chemical, so boosting it can improve mood, physical well-being, behavior, and overall outlook. Because of this effect, fluoxetine can be used to treat a wide range of mental health conditions, including:

Depression
Obsessive-compulsive disorder (OCD)
Anxiety disorders
Panic attacks
Premenstrual dysphoric disorder (PDD)

Fluoxetine may also be used alongside a medication called “olanzapine” to manage treatment-resistant depression, and even episodes of depression in people with bipolar I disorder.²

It’s important to bear in mind that fluoxetine has been linked to suicidal thoughts in a small number of people. What’s more, the younger someone is, the more prone they may be to these thoughts. Although studies have shown that this risk is likely minimal, it’s still important to carefully monitor thoughts and behaviors when starting fluoxetine – and any other antidepressant.³Mission Connection can advise you or a loved one on this risk.

To help you determine whether fluoxetine may be helpful for your symptoms, let’s take a closer look at its benefits for depression, anxiety, and OCD.

Fluoxetine Dosage for Depression

Fluoxetine is commonly prescribed for depression as it has been shown to be beneficial in reducing symptoms and is considered to be well tolerated by the majority of people.⁴ Due to a boost in serotonin, people taking fluoxetine for depression often feel improved mood and outlook, and reduced hopelessness.

Fluoxetine can be taken in either capsule, delayed-release capsule, tablet, or solution form for depression. Dosage will differ from person to person, depending on specific needs and symptoms. It’s important that you follow your doctor’s instructions. If in doubt, the medication comes with directions, or you could phone your provider.

A doctor will also likely start with a low dose of fluoxetine and increase the amount as required.

Fluoxetine for Anxiety

Fluoxetine is more commonly prescribed for panic disorders than for generalized or social anxiety.5 However, due to its ability to increase the amount of serotonin in the brain, it has the potential to benefit most people with anxiety. Yet, there’s a lack of scientific evidence to back these benefits up.6 Additionally, while SSRIs generally improve the symptoms of anxiety, they can also worsen them – especially in the early stages of treatment.⁷

If you’re interested in taking fluoxetine for anxiety, discuss your symptoms with your medical or mental health provider to determine its suitability for your needs.

Fluoxetine for OCD

OCD is a distressing disorder which is marked by recurring, unwanted, and repetitive thoughts and behaviors. Fluoxetine has proven to be valuable in reducing the symptoms of OCD for many people, including obsessive thoughts, compulsive actions, and anxiety. Due to this effect, and how it tends to be well-tolerated by many people, fluoxetine is often the “go-to” medication for treating OCD.⁸

However, people with OCD may require a slightly higher dosage of fluoxetine than those with depression to see benefits. Due to this higher dose, there may be an increased risk of side effects, so it’s good to consult with a healthcare provider about these risks.

How Long Does Prozac Take to Work?

Truthfully, the answer to “How long does Prozac take to work?” isn’t straightforward. It takes time for the chemicals in the brain to adjust, and everyone responds differently to medication due to their unique physical makeup and symptoms.

Some people might start to see the benefits at the one-week mark, but others might have to wait until roughly six weeks.⁹ This might not be the answer you want to hear right now, but try not to be discouraged. If you don’t see results after the initial adaptation period, talk to your healthcare provider about either upping your dose or switching medications.

However, the signs that fluoxetine is working can initially be subtle, so the following indicators can help you recognize if it is.

Signs Fluoxetine Is Working:¹⁰

Fewer feelings of anxiety
Improved sleep and energy
Better appetite
Improved focus
More balanced moods
Reduced physical symptoms
Increased interest in activities
Better overall outlook

The key with any antidepressant is to be patient – the more severe the symptoms, the slower they can be to shift. However, therapy, such as cognitive behavioral therapy (CBT), has been proven to complement medication and improve outcomes for a variety of conditions.11 Therefore, you may see quicker results through a combination approach to treatment. Mission Connection can advise you on this approach.

What Are the Common Side Effects of Fluoxetine?

SSRIs are considered to be the first-line medication for treating the majority of mental health issues due to their lower risk of side effects. But all medications come with potential complications, and fluoxetine is no exception. Moreover, the same medication can affect two people differently.

Antidepressants require regular monitoring to make sure that there are no adverse side effects for your well-being. For instance, if you experience any of the following side effects, it’s important to communicate this with your health care provider so that the dosage or medication can be adjusted.

Fluoxetine Side Effects:^2,12

Gastrointestinal issues, such as stomach upset or diarrhoea
Headache
Perspiration
Dry mouth
Heartburn
Anxiety and nervousness
Difficulty sleeping
Brain “zaps”
Changes in weight and appetite
Sexual dysfunction

As previously mentioned, an additional side effect of fluoxetine could be suicidal thoughts. If this is the case for you or a loved one, it’s important to immediately contact your health care provider. If there’s an immediate risk to physical well-being, calling 911 or going to the nearest emergency department is the best option.

Stopping Prozac Safely: Can I Stop Taking Fluoxetine Abruptly?

There’s a wide range of reasons why people may want to stop taking their medications. You may no longer experience symptoms, find that they’re becoming too expensive, experience too many side effects, or feel like they’re not working.

However, if you want to come off fluoxetine, it’s important to do so safely. Depending on your dosage and how long you’ve been on antidepressants, suddenly stopping them could set you up for prozac withdrawal symptoms. Prozac withdrawal isn’t typically fatal, but it is highly unpleasant and could lead to a setback in your recovery.

Prozac withdrawal symptoms include:¹³

Return of emotional and mental symptoms
Insomnia
Sweating
Stomach upset
Brain jolts (feeling like there’s an electric shock in your head)
Dizziness
Agitation
Flu-like symptoms

If you’re wondering how to taper off fluoxetine, the answer is “slowly.” Prozac discontinuation can lead to an increase in anxious and depressive thoughts. This doesn’t mean you’re addicted, but your body and mind will need time to adjust.¹⁴ Mission Connection can help you create a tapering plan that promotes your recovery rather than knocks it back.

How Long Does Fluoxetine Stay In Your System?

Fluoxetine is a long-acting antidepressant. This means that it can take a long time to leave your body. In other words, if you suddenly stop taking Prozac, you might not notice withdrawal symptoms for a few days – or even weeks.¹⁵ But this doesn’t mean they won’t come. What’s more, your brain may trick you into thinking that they won’t, which means that prozac withdrawal symptoms could take you off guard.

The best offence is a good defence: No matter how low your dose, if you want to come off fluoxetine, it’s best to taper it under medical guidance. For instance, a mental health professional can reduce your dosage gradually and monitor your physical and emotional reactions. If, after a certain time period – say a month – they deem you to be stable, they may aim to lower it again. And so on and so forth until the drug has left your system.

Monitoring discontinuation of Prozac in this way allows you and your mental health professional to quickly recognize issues before they become big problems – protecting your mental and physical well-being.

Questions to Ask Your Healthcare Provider About Fluoxetine

Making the decision to take Prozac for a mental health condition shouldn’t be taken lightly, as it comes with a certain amount of risks and challenges. However, when it’s a good fit for your needs and symptoms, it can offer emotional and physical relief.

To make sure you’re going into this decision with your eyes open, the following frequently asked questions cover topics this article hasn’t previously covered.

Fluoxetine vs Sertraline: Which Is Better?

There’s no clear answer on whether fluoxetine (Prozac) is better than sertraline (Zoloft). It all comes down to what your symptoms are and how you respond to the medication. For instance, Zoloft may be more appropriate for PTSD, while Prozac might be a better option for depression in bipolar disorder. The side effects of both meds might also differ, with Prozac sometimes causing more headaches and lack of energy in comparison to Zoloft’s higher rates of nausea and sexual dysfunction.

Mission Connection can discuss the option of fluoxetine vs sertraline for your needs. Sometimes, a process of trial and error is needed to find the best fit, as only your reactions can give the correct answer.

How Suitable Is Fluoxetine for Teens?

The National Institute of Health and Care Research reports that Prozac may be the best choice for teenagers with symptoms of depression – especially when it is combined with CBT.¹⁶ However, the study also highlights that providers need to treat each case on an individual basis; just because fluoxetine works for one teen, it doesn’t mean it will benefit another. Plus, it’s especially important to keep an eye out for suicidal thoughts and self-harm behaviors in response to early SSRI treatment.

Does Prozac Cause Weight Gain?

Many people are either hesitant to start or want to stop taking antidepressants due to potential weight gain. This is a reasonable concern – it’s important to feel confident and have some control over your physical health. However, while antidepressants are associated with small weight gain, this is a very manageable amount. Further, fluoxetine is one of the SSRIs linked to the least weight gain.¹⁷ If you’re concerned about weight and antidepressants, Mission Connection can help you create healthy lifestyle plans for managing this effect.

Can Fluoxetine Cause Insomnia?

Many people with conditions such as anxiety and depression suffer from sleep disturbances like insomnia, which can create further problems with daily functioning and significant distress. Therefore, antidepressants may seem like a “cure” for sleep problems.

Unfortunately, fluoxetine is linked to insomnia and poorer quality sleep in general.¹⁸ This comes down to its “activating” or “stimulating” effect on the brain. The good news is that sleep disturbances usually go away as the brain adapts to the medication – but this might not be the case for everyone. If fluoxetine continues to affect your sleep, your provider may switch you to another drug.

Mission Connection: Supporting You Through Holistic Care

Fluoxetine is an SSRI antidepressant that can help manage the symptoms of a range of mental health conditions, including depression, panic disorders, OCD, and treatment-resistant depression. But it shouldn’t be thought of as a “magic pill.”

Antidepressants often play an important role in getting symptoms under control, but they don’t target the root of the problem. Mission Connection does. Our team of trained professionals can support you with medication management while also targeting the thoughts, experiences, and emotions that fuel your challenges.

We offer a variety of treatment options and therapy, ranging from residential treatment to online telehealth services – making sure you’re supported even when your schedule is demanding.

If you’re curious about Mission Connection’s treatment options or just have more questions to ask about medication, our team is here to help. Contact us today at 866-561-4108 or fill out our confidential contact form.

References

Gerriets, V., Anderson, J., & Nappe, T. M. (2021, July 3). Acetaminophen. In StatPearls. StatPearls Publishing. https://www.ncbi.nlm.nih.gov/books/NBK459223/
National Library of Medicine. (2022, January 15). Fluoxetine. MedlinePlus. https://medlineplus.gov/druginfo/meds/a689006.html
D Gibbons, D. R., Hendricks Brown, D. C., Hur, D. K., M Davis, D. J., & John Mann, D. J. (2012). Suicidal Thoughts and Behavior With Antidepressant Treatment: Reanalysis of the Randomized Placebo-Controlled Studies of Fluoxetine and Venlafaxine. Archives of General Psychiatry, 69(6), 580. https://doi.org/10.1001/archgenpsychiatry.2011.2048
Reyad, A. A., Plaha, K., Girgis, E., & Mishriky, R. (2020). Fluoxetine in the Management of Major Depressive Disorder in Children and Adolescents: A Meta-Analysis of Randomized Controlled Trials. Hospital Pharmacy, 56(5), 525. https://doi.org/10.1177/0018578720925384
National Library of Medicine. (2024, November 13). PROZAC – fluoxetine hydrochloride capsule. DailyMed. https://dailymed.nlm.nih.gov/dailymed/drugInfo.cfm?setid=c88f33ed-6dfb-4c5e-bc01-d8e36dd97299&audience=consumer
Strawn, J. R., Geracioti, L., Rajdev, N., Clemenza, K., & Levine, A. (2018). Pharmacotherapy for Generalized Anxiety Disorder in Adults and Pediatric Patients: An Evidence-Based Treatment Review. Expert Opinion on Pharmacotherapy, 19(10), 1057. https://doi.org/10.1080/14656566.2018.1491966
Gollan, J. K., Fava, M., Kurian, B., Wisniewski, S. R., Rush, A. J., Daly, E., Miyahara, S., & Trivedi, M. H. (2011). What Are the Clinical Implications of New Onset or Worsening Anxiety During the First Two Weeks of SSRI Treatment for Depression? Depression and Anxiety, 29(2), 10.1002/da.20917. https://doi.org/10.1002/da.20917
Etain, B., & Bonnet-Perrin, E. (2001). Intérêt de la fluoxétine dans les troubles obsessionnels et compulsifs de l’adulte: Revue de la littérature [Value of fluoxetine in obsessive-compulsive disorder in the adult: Review of the literature]. L’Encéphale, 27(3), 280–289. https://pubmed.ncbi.nlm.nih.gov/11488259/
Chu, A., & Wadhwa, R. (2023). Selective serotonin reuptake inhibitors. In StatPearls. StatPearls Publishing. https://www.ncbi.nlm.nih.gov/books/NBK554406/
Drugs.com. (2024, October 29). What does Prozac feel like when it starts working? https://www.drugs.com/medical-answers/prozac-feel-starts-working-3571159/
Gautam, M., Tripathi, A., Deshmukh, D., & Gaur, M. (2020). Cognitive Behavioral Therapy for Depression. Indian Journal of Psychiatry, 62(Suppl 2), S223. https://doi.org/10.4103/psychiatry.IndianJPsychiatry_772_19
Ferguson, J. M. (2001). SSRI Antidepressant Medications: Adverse Effects and Tolerability. Primary Care Companion to The Journal of Clinical Psychiatry, 3(1), 22. https://doi.org/10.4088/pcc.v03n0105
Gabriel, M., & Sharma, V. (2017). Antidepressant discontinuation syndrome. CMAJ : Canadian Medical Association Journal, 189(21), E747.
Harvard Health Publishing. (2022, May 15). Going off antidepressants. Harvard Health. https://www.health.harvard.edu/diseases-and-conditions/going-off-antidepressants
Royal College of Psychiatrists. (n.d.). Stopping antidepressants. https://www.rcpsych.ac.uk/mental-health/treatments-and-wellbeing/stopping-antidepressants
NIHR Evidence. (2020, October 12). Prozac may be the best treatment for young people with depression – but more research is needed. https://evidence.nihr.ac.uk/alert/prozac-may-be-the-best-treatment-for-young-people-with-depression-but-more-research-is-needed/
Salamon, M. (2024, August 2). Weighing in on weight gain from antidepressants. Harvard Health Publishing. https://www.health.harvard.edu/blog/weighing-in-on-weight-gain-from-antidepressants-202408023063
Dorsey, C. M., Lukas, S. E., & Cunningham, S. L. (1996). Fluoxetine-induced sleep disturbance in depressed patients. Neuropsychopharmacology, 14(6), 437–442. https://doi.org/10.1016/0893-133X(95)00148-7