Prozac for anxiety dosage
Prozac For Anxiety: Dosage, Side Effects, Interactions & More
Anxiety is a normal human emotion, but when someone experiences intrusive, intense anxiety symptoms that impacts their daily life, they may have an anxiety disorder.
Anxiety disorders are the most common mental health condition in the United States. By some estimates, more than 40 million Americans, or 18% of our population, will have an anxiety disorder at some point in their lives.
Fortunately, there are several prescription medications available for patients who need help managing their symptoms. Prozac (fluoxetine) is one of several antidepressant medications that can be a great option for treating anxiety.
Prozac has been FDA-approved for the treatment of major depressive disorder (MDD), obsessive compulsive disorder (OCD), and depressive episodes related to bipolar I disorder in both adults and children. It is also approved for adults suffering from panic disorder, bulimia nervosa, and treatment-resistant depression.
It can also sometimes be prescribed for social anxiety disorder (SAD), premenstrual dysphoric disorder (PMDD), generalized anxiety disorder (GAD), and post-traumatic stress disorder (PTSD).
In this article, I’ll explain what Prozac is, and how it works for anxiety. I’ll outline the dosage of the drug used for anxiety, how quickly it works, and whether it works for social anxiety.
I’ll explain whether teenagers can take the drug, and how adults and children should take it. I’ll also describe the drug’s side effects, list possible drug interactions and warnings, and lay out the risks of taking Prozac. Finally, I’ll discuss other options that are available if this medication isn’t right for you.
Take our free assessment and learn about your options.
What is Prozac?
Prozac (fluoxetine) is one of a class of antidepressant medications called selective serotonin reuptake inhibitors (SSRIs), which work by increasing the level of serotonin in the brain.
Serotonin is a neurotransmitter that passes messages between nerve cells and positively influences our emotions, appetite, and sleep, among other things. In a normal situation, once it has conveyed its message, serotonin is reabsorbed back into the brain.
When someone takes an SSRI like Prozac, however, the drug blocks their brain from reabsorbing—”reuptaking”—serotonin, leaving more available for continued use.
Prozac was brought to market as a brand-name prescription in the late 1980s after the Food and Drug Administration (FDA) approved it to treat patients who had clinical depression.
Since that time, the FDA has additionally approved Prozac to treat major depressive disorder (MDD), bulimia nervosa, and certain anxiety disorders.
Additionally, it is sometimes combined with other medications to treat patients who have bipolar disorder or who experience a kind of major depression that is otherwise treatment-resistant.
Does Prozac Work for Anxiety?
Prozac does not cure anxiety disorders, but it is considered a safe and effective way to help patients manage their anxiety-related symptoms. It has been FDA-approved to treat patients with:
- Panic disorder: An anxiety disorder that causes patients to suffer from regular, spontaneous, and extreme bouts of fear or terror called panic attacks.
- Obsessive-compulsive disorder (OCD): An anxiety disorder in which patients are impacted by intrusive thoughts or sensations (called obsessions) and develop repetitive behavioral patterns—called compulsions—in an ineffective attempt to stave them off.
Clinical trials are still testing Prozac’s efficacy with anxiety disorders that it has not been FDA-approved to treat. In the meantime, mental health professionals will often prescribe the drug “off-label” to help address conditions like generalized anxiety disorder (GAD), social anxiety disorder (SAD), persistent depressive disorder, and post-traumatic stress disorder (PTSD).
Directing patients to take off-label medication is legal and safe, as long as the doctor uses their professional discretion.
How Does Prozac Work for Anxiety?
Prozac is widely considered an effective, first-line treatment option for people who suffer from certain types of anxiety disorders.
By increasing the availability of serotonin in the brain, the drug helps improve mood, regulate emotions, increase quality sleep, and boost appetite. These changes, in turn, can help calm the nervous system and make it less reactive.
Mental health professionals often prescribe SSRIs like Prozac because they are less likely to have serious side effects than other medications.
In addition, when used on its own or in conjunction with other treatments like psychotherapy, Prozac can help anxious patients relax and enjoy a higher quality of life.
Prozac Dosage for Anxiety
Every patient is different. Individual dosages can vary depending on the person taking the medication, their general health, age, and the nature of their anxiety disorder.
- Obsessive-compulsive disorder (OCD): It is recommended that most patients with OCD should begin by taking 20 mg of Prozac by mouth every day. If your doctor believes you would benefit from a higher dose, they will gradually increase it by 20 mg over every few months. As a rule, patients should not take more than 80 mg by mouth a day when treating OCD.
- Panic Disorder: It’s recommended that most patients with panic disorder should begin by taking 10 mg of Prozac by mouth every day before their dose is gradually increased to 20 mg and beyond. Patients with panic disorders should not take more than 60 mg by mouth a day to treat their condition.
Prozac is also approved for pediatric patients over the age of 7 with obsessive-compulsive disorder.
Most pre-adolescent children should begin taking 10 mg of medication by mouth every day before their dosage increases to 20 mg after two weeks of treatment, while adolescents may be prescribed doses as high as 60 mg daily.
If you or your child has anxiety and are wondering what dosage might help manage those symptoms, please seek medical advice from a healthcare professional.
How Quickly Does Prozac Work?
If you began to take Prozac recently and have yet to feel its effects, don’t worry. Like other antidepressant medications, you have to take Prozac for some time before you begin to feel better.
While some patients report a decrease in their anxiety symptoms after just a few weeks of regularly taking the medication, most do not experience relief until 6 to 8 weeks into their treatment.
It’s important to remember that once you start Prozac, it can cause withdrawal symptoms if you abruptly stop taking it. If you have been taking Prozac for a while and don’t feel like it is helping you, make an appointment with your doctor—but continue taking the medication as prescribed until you see them.
Once they medically evaluate you, your doctor may recommend a higher dose to make the Prozac more effective for you, or they may gradually taper off the medication to help you avoid withdrawal while changing to a different treatment.
Currently, Prozac is only FDA-approved to treat two specific anxiety disorders: obsessive-compulsive disorder and panic disorder. Anecdotal evidence suggests that Prozac also works to help patients with a social anxiety disorder (SAD) when prescribed “off-label,” but scientific research is still inconclusive. Some studies suggest that Prozac is an effective treatment for people who have social phobias, while others have found that the medication is no more helpful than a placebo.
Can Teenagers be Treated with Prozac?
Many children and teens with anxiety and depression find that Prozac helps them manage their symptoms safely. Prozac is FDA-approved to treat patients ages 7-18 with obsessive-compulsive disorder and pediatric patients ages 8-18 who have major depressive disorder (MDD).
If you or someone you know is taking Prozac or another SSRI like sertraline hydrochloride (Zoloft), you should be aware that for a small number of pediatric patients, these medications can cause an increase in suicidal thoughts and behaviors.
If you or your loved one is showing any indication that they pose a risk to themselves or others, call 9-1-1 or immediately go to the nearest emergency room.
How to Take Prozac
Prozac is available in four forms: a tablet, capsule, time-release capsule, and oral solution. Whatever form your prescription comes in, be sure to take your dosage precisely as directed and only once a day.
You can take your medication in the morning, afternoon, or evening, as long as it’s around the same time every day. Prozac can be taken with or without food.
It’s estimated that 80% of patients experience at least one side effect while taking an antidepressant. Most of these effects are mild, and most patients are not bothered enough by their symptoms to stop taking their medication.
People who take Prozac can experience a range of common side effects, including:
- Abnormal dreams
- Dry Mouth
- Heart palpitations
- Impaired judgment or motor skills
- Increased appetite
- Loss of appetite
- Sore throat
- Stuffy nose
- Weight gain
- Weight loss
Many patients who take Prozac have also reported sexual side effects, including sexual dysfunction (impotence), abnormal ejaculation, decreased libido, and other sexual problems.
In rare cases, patients can have an allergic reaction to Prozac. If you are taking the medication and begin to experience hives, shortness of breath, facial swelling, heat, or skin rash, seek emergency medical attention immediately.
Prozac can interact with a variety of other prescription medications, over-the-counter medications, and homeopathic remedies.
To avoid adverse drug interactions, be sure to tell your doctor about everything you take before beginning to take Prozac or any other antidepressant.
Drugs that interact poorly with Prozac include:
- Monoamine oxidase inhibitors (MAOIs)
- NSAIDs including aspirin and warfarin
- St. John’s wort
- Tricyclic antidepressants
Never take Prozac with another SSRI or serotonergic medication. Taking multiple drugs that boost your serotonin levels can put you at risk for developing serotonin syndrome, a rare but severe condition that can cause tremors, palpitations, muscle rigidity, agitation, confusion, and seizures.
If you experience any of those symptoms, go to the emergency room right away as serotonin syndrome can be a life-threatening condition.
Prozac is not for everyone. For a small segment of the population, it can contribute to adverse health outcomes, including:
- Increased risk of suicide
- Allergic reaction
- Mania or hypomania
- Significant weight loss
- Abnormal bleeding
- Worsening anxiety
- Impaired Judgement
If you are taking Prozac and are worried about any physical or mental challenges that you believe might be caused or exacerbated by the medication, call your doctor to share your concerns.
If you’re having a mental health emergency, call 911 or go to the nearest emergency room. You can also get free 24/7 support from a suicide and crisis expert by calling or texting 988. If you’d prefer to chat online, you can chat with a suicide and crisis expert by visiting the Lifeline Chat.
Women who are pregnant or breastfeeding, or become pregnant while taking Prozac, should talk to their doctor about the risks involved.
The medication poses some rare but serious risks to unborn and nursing children, and the risks and benefits should be discussed with your doctor as well as your obstetrician-gynecologist (OB-GYN).
Take our free assessment and learn about your options.
If you suffer from an anxiety disorder and find that Prozac is not the right option for you, don’t worry. There are other treatments that you can use to manage your symptoms and improve your quality of life. They include:
- Selective serotonin reuptake inhibitors: Prozac is only one of many SSRIs approved to treat people with anxiety. Doctors can also prescribe paroxetine (Paxil) and sertraline hydrochloride (Zoloft) for specific anxiety disorders.
- Serotonin and norepinephrine reuptake inhibitors: Certain SNRI medications like duloxetine (Cymbalta) and venlafaxine (Effexor XR) have been FDA-approved to treat certain anxiety disorders.
- Benzodiazepines: Doctors commonly prescribe sedative medications like diazepam (Valium), alprazolam (Xanax), and lorazepam (Ativan) to help patients with anxiety challenges.
How K Health Can Help?
Think you might need a prescription for Prozac (fluoxetine)?
K Health has clinicians standing by 24/7 to evaluate your symptoms and determine if Prozac is right for you.
Get started with our free assessment, which will tell you in minutes if treatment could be a good fit. If yes, we’ll connect you right to a clinician who can prescribe medication and have it shipped right to your door.
Frequently Asked Questions
Can Prozac make anxiety worse?
When most people with anxiety disorders like OCD and panic disorders take Prozac, they find that it helps them manage their symptoms and improve their quality of life. However, in rare cases, the medication can cause adverse side effects, including increased anxiety or nervousness.
Is 10 mg of Prozac enough for anxiety?
Everyone is different, and individual dosage depends on who is taking the Prozac, their age, and the nature of their condition. For some, 10 mg is an effective dose of medication. Others may need to talk to their doctor about gradually increasing their dosage until they get to a dose that’s effective for them.
K Health articles are all written and reviewed by MDs, PhDs, NPs, or PharmDs and are for informational purposes only. This information does not constitute and should not be relied on for professional medical advice. Always talk to your doctor about the risks and benefits of any treatment.
K Health has strict sourcing guidelines and relies on peer-reviewed studies, academic research institutions, and medical associations. We avoid using tertiary references.
Fluoxetine (including Prozac). (2018).
A brief history of the development of antidepressant drugs: From monoamines to glutamate. (2016).
Prozac (fluoxetine hydrochloride) capsules label. (Date Unknown).
Facts and Statistics. (2021).
Fluoxetine (Prozac). (2020).
Fluoxetine efficacy in social phobia. (1993).
Fluoxetine in social phobia: a double-blind, placebo-controlled pilot study. (2002).
Managing the Adverse Effects of Antidepressants. (2014).
Key Findings—A Closer Look at the Link Between Specific SSRIs and Birth Defects. (2020).
Prozac For Anxiety: Benefits, Dosage, Side Effects, and More
Medically reviewed by Kristin Hall, FNP
Written by Our Editorial Team
Last updated 7/10/2022
It’s normal to feel anxious from time to time, especially in stressful situations. However, if you’re prone to severe or persistent anxiety, or if you frequently experience panic attacks, you may be one of the tens of millions of American adults with an anxiety disorder.
Several medications are available to treat anxiety disorders, including the antidepressant drug Prozac®.
Prozac, which contains the active ingredient fluoxetine, works by affecting the levels of natural chemicals that control your moods and feelings. Taken consistently, it can help to treat several common forms of anxiety, improving your mental well-being and quality of life.
Below, we’ve explained what Prozac is, as well as how Prozac and similar medications work to treat the symptoms of anxiety.
We’ve also explained how you can use Prozac for anxiety, from approved dosages to potential side effects and drug interactions that you should be aware of before you start treatment.
What Is Prozac?
Prozac is an antidepressant that contains the active ingredient fluoxetine. It belongs to a class of drugs called selective serotonin reuptake inhibitors (SSRIs).
The FDA first approved Prozac in 1987 as a medication for treating major depressive disorder (MDD). Prozac is also approved to treat PMDD (premenstrual dysphoric disorder), obsessive-compulsive disorder (OCD), panic disorder, bipolar disorder and bulimia nervosa.
Like many other medications, Prozac is often prescribed off-label to treat conditions other than those approved by the FDA.
Common off-label uses of Prozac include the treatment of:
Social anxiety disorder (SAD, or social phobia)
Post-traumatic stress disorder (PTSD)
Borderline personality disorder
As an SSRI, Prozac works by increasing the amount of serotonin — a type of naturally-occurring chemical called a neurotransmitter — that’s active in your brain and body.
Serotonin is involved in regulating your mood, happiness and levels of anxiety. It also plays an important role in regulating your sleep cycle and general mental health. Low levels of serotonin are associated with an increased risk of mental health disorders, including anxiety.
By increasing serotonin levels, Prozac may reduce the severity of anxiety symptoms and make it easier for you to maintain a normal life.
Does Prozac Help With Anxiety?
Prozac doesn’t treat every form of anxiety, but it can provide real benefits for people with certain anxiety conditions.
Prozac is approved by the FDA to treat panic disorder — a common type of anxiety disorder that involves intense periods of fear, discomfort and loss of control called panic attacks.
It’s also commonly used as an off-label treatment for social anxiety disorder — another common anxiety disorder that involves intense, persistent fears in social situations, such as public events and auditions.
Prozac isn’t a cure for anxiety, and using it doesn’t guarantee that you’ll never have to deal with panic attacks, intrusive thoughts, compulsive behavior or other problems again. Nor is it always the best treatment option for every type of anxiety disorder.
However, when it’s taken appropriately and consistently, Prozac may make it easier to manage some anxiety and major depression symptoms.
Over the decades, numerous studies have looked at the effects of Prozac as a treatment option for anxiety.
During clinical trials, researchers found that Prozac significantly increased the number of people with panic disorder who reported an end to their panic attacks.
In one randomized trial involving 180 participants, Prozac produced a significant increase in the number of people who were free of panic attacks after 12 weeks (42 percent, versus 28 percent for a non-therapeutic placebo).
A similar flexible-dose trial involving 214 people produced similar findings, with 62 percent of the participants experiencing an end to panic attacks while using Prozac compared to 44 percent of people who used a non-therapeutic placebo.
Research into the effectiveness of Prozac for other forms of anxiety is mixed, with some studies showing positive effects and others showing limited changes:
One study of fluoxetine (the active ingredient in Prozac) for social anxiety published in the journal Archives of General Psychiatry concluded that it was more effective than a placebo and comparable to cognitive behavioral therapy (CBT).
A general meta-analysis of selective serotonin reuptake inhibitor medications (SSRIs) and social anxiety found that medications of this type, including Prozac, can offer real benefits, including improved scores in certain social functioning scales.
However, a double-blind, placebo-controlled study involving 60 people published in the Journal of Clinical Psychopharmacology found that Prozac was no more effective than placebo treatments for social phobia.
A small trial published in the Journal of the American Academy of Child and Adolescent Psychiatry in 2003 found that fluoxetine was effective and well-tolerated as a treatment for generalized anxiety, separation anxiety disorder and social phobia in youths.
However, this study only involved individuals from seven to 17 years of age, and did not feature any adult participants.
A literature review of Chinese patients published in the journal Neuropsychiatric Disease and Treatment in 2013, which used data from 15 open-label, non-placebo trials, stated that Prozac was comparable in efficacy to other anxiety medications.
However, the researchers noted that existing research on Prozac for anxiety has a high risk of bias, and that small sample sizes and a lack of placebo groups make it difficult to draw any firm conclusions from existing studies.
Overall, there’s strong evidence that Prozac is helpful for panic disorder, with mixed findings on its potential benefits for social anxiety, generalized anxiety disorder and other forms of anxiety.
How Quickly Does Prozac Work for Anxiety?
Prozac is generally an effective medication for social anxiety, post-traumatic stress disorder and other conditions that involve anxiety. However, it doesn’t deliver instant relief, meaning you won’t feel calm and relaxed right away.
It can take four to five weeks for Prozac to start working fully. During this time, you may begin to experience small, gradual improvements in some anxiety symptoms, including your feelings and general moods.
It’s important to not to stop taking Prozac if you don’t notice improvements during the first four to five weeks. Be patient and keep using Prozac — over time, you’ll start to notice improvements as the medication becomes more effective.
Prozac Dosage for Anxiety
Prozac is typically prescribed at a dosage of 10 to 20mg daily for panic disorder and 20mg per day for obsessive-compulsive disorder. Your healthcare provider may adjust this dosage over time based on your response to Prozac, your risk of side effects and other factors.
Most people respond well to Prozac at a dosage of 20 to 40mg daily. The maximum dosage of Prozac is 80mg per day.
There’s currently no precise dosage of Prozac for off-label uses, such as obsessive-compulsive disorder or social anxiety disorder.
If you’re prescribed Prozac for off-label use, your healthcare provider may instruct you to start at a low dosage, then adjust your dosage over time.
Related post: Is Prozac Addictive?
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Prozac Side Effects and Interactions
Like other antidepressants, Prozac can cause side effects. It’s important to let your healthcare provider know if you have any side effects that are severe, bothersome or do not improve over time.
Common side effects of Prozac include:
Asthenia (physical weakness)
Pharyngitis (sore throat)
Many adverse effects of Prozac improve gradually as your body starts to adjust to the effects of this medication.
Like other SSRIs, Prozac can cause sexual side effects, including sexual dysfunction in women and men. While using Prozac, you may notice that your sex drive is weaker than normal, or that you find it more difficult to reach orgasm during sexual activity.
Prozac can interact with other medications. When used with medications that increase serotonin levels, Prozac may cause a potentially dangerous drug interaction called serotonin syndrome, in which serotonin levels increase beyond a safe level.
Serotonin syndrome can cause serious, potentially harmful symptoms, including elevated blood pressure, heart palpitations, tremor, shivering, muscle jerking and overly active reflexes. Severe cases of serotonin syndrome may cause renal failure, blood clots, coma and even death.
Medications and supplements that may interact with Prozac include:
Tricyclic antidepressants (TCAs)
Monoamine oxidase inhibitors (MAOIs)
SSRIs and other antidepressants
Fentanyl, tramadol and other opioid pain medications
Anxiety medications, such as buspirone (Buspar®)
St. John’s wort
To reduce your risk of experiencing serotonin syndrome or other drug interactions, make sure to inform your healthcare provider about any medications you currently take or have recently taken before starting treatment with Prozac.
It’s especially important to inform your healthcare provider if you’ve used an MAOI or other type of antidepressant medication to treat any medical conditions within the last 14 days.
If you're concerned about an interaction with your ADHD medication, you can read our blog on Prozac and Adderall.
How to Use Prozac for Anxiety
Prozac is an easy medication to use. It’s available as a capsule, a tablet and as a solution. Most people take Prozac one time each day in the morning. Your healthcare provider will inform you about when to take Prozac and how much medication to take each day.
Use the following tips to get the best results from Prozac as an anxiety treatment:
Take Prozac at around the same time every day. Prozac works best when it’s taken at a consistent time of day. Try to follow your healthcare provider’s instructions as closely as you can and aim to take Prozac at around the same time daily.
If you miss a dose, take it as soon as you remember. However, if it’s almost the right time for your next dose of Prozac, skip the missed dose and continue as normal. Do not take two doses of Prozac at once to make up for a missed dose.
Combine Prozac with psychotherapy. Prozac and other antidepressants often have a greater effect when they’re combined with certain forms of talk therapy, such as cognitive behavioral therapy (CBT).
Your healthcare provider may recommend meeting with a therapist. We also offer online therapy, allowing you to connect with a licensed provider from the privacy and comfort of your home.
Wait two to four weeks before assessing your results from Prozac. It usually takes two to four weeks for Prozac to start working properly, during which you may not notice any improvements in your moods, feelings or anxiety symptoms.
When you start taking Prozac, be patient. Try to wait for at least four weeks before you start assessing your results.
If Prozac doesn’t work for you, don’t worry. It’s normal to try several antidepressants before finding the right one for you. If Prozac doesn’t seem to work well for you after two to four weeks, don’t panic. Instead, let your healthcare provider know.
Your healthcare provider may adjust your dosage or recommend switching to a different antidepressant or anti-anxiety medication that’s better suited to your needs.
Never stop taking Prozac abruptly. When Prozac is stopped abruptly, it can potentially cause withdrawal symptoms, including mood changes, dizziness, agitation, sleep issues, headaches and a return of your anxiety symptoms.
If Prozac isn’t working, don’t stop taking it abruptly. Instead, let your healthcare provider know that you’d like to stop treatment. They’ll help you to slowly taper your dosage and stop using Prozac safely.
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Learn More About Treating Anxiety
Prozac is a popular, effective medication for treating panic disorder, a common form of anxiety that can involve sudden panic attacks. However, research findings are mixed when it comes to using Prozac for social anxiety or generalized anxiety disorder.
If you’re prescribed Prozac for anxiety, make sure to closely follow your mental health provider’s instructions and inform them if you experience any side effects.
Interested in learning more about dealing with anxiety? We offer a full range of medications for anxiety and depression online, which are available following a private online consultation with a psychiatry provider who will determine if a prescription is appropriate.
We also offer other mental health services, including individual online therapy and anonymous online support groups.
You can also learn more about successfully coping with anxiety, depression, severe stress and other mental health concerns using our free online mental health resources and content.
Hims & Hers has strict sourcing guidelines to ensure our content is accurate and current. We rely on peer-reviewed studies, academic research institutions, and medical associations. We strive to use primary sources and refrain from using tertiary references.
- PROZAC (fluoxetine capsules) for oral use. (2017, January). Retrieved from https://www.accessdata.fda.gov/drugsatfda_docs/label/2017/018936s108lbl.pdf
- Sohel, A.J., Shutter, M.C. & Molla, M. (2022, May 2). Fluoxetine. StatPearls. Retrieved from https://www.ncbi.nlm.nih.gov/books/NBK459223/
- Brain Hormones. (2022, January 23). Retrieved from https://www.endocrine.org/patient-engagement/endocrine-library/hormones-and-endocrine-function/brain-hormones
- Davidson, J.R., et al. (2004, October). Fluoxetine, comprehensive cognitive behavioral therapy, and placebo in generalized social phobia. Archives of General Psychiatry. 61 (10), 1005-1013. Retrieved from https://pubmed.ncbi.nlm.nih.gov/15466674/
- Hedges, D.W., et al. (2007, January). The efficacy of selective serotonin reuptake inhibitors in adult social anxiety disorder: a meta-analysis of double-blind, placebo-controlled trials. Journal of Psychopharmacology (Oxford, England). 21 (1), 102-111. Retrieved from https://pubmed.ncbi.nlm.nih.gov/16714326/
- Kobak, K.A., Greist, J.H., Jefferson, J.W. & Katzelnick, D.J. (2002, June). Fluoxetine in social phobia: a double-blind, placebo-controlled pilot study. Journal of Clinical Psychopharmacology. 22 (3), 257-262. Retrieved from https://pubmed.ncbi.nlm.nih.gov/12006895/
- Birhamer, B., et al. (2003, April). Fluoxetine for the treatment of childhood anxiety disorders. Journal of the American Academy of Child and Adolescent Psychiatry. 42 (4), 415-423. Retrieved from https://pubmed.ncbi.nlm.nih.gov/12649628/
- Zou, C., Ding, X., Flaherty, J.H. & Dong, B. (2013). Clinical efficacy and safety of fluoxetine in generalized anxiety disorder in Chinese patients. Neuropsychiatric Disease and Treatment. 9, 1661-1670. Retrieved from https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3818099/
- Volpi-Abadie, J., Kaye, A.M. & Kaye, A.D. (2013). Serotonin Syndrome. The Ochsner Journal. 13 (4), 533-540. Retrieved from https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3865832/
- Anxiety Disorders. (2022, April). Retrieved from https://www.nimh.nih.gov/health/topics/anxiety-disorders
This article is for informational purposes only and does not constitute medical advice. The information contained herein is not a substitute for and should never be relied upon for professional medical advice. Always talk to your doctor about the risks and benefits of any treatment. Learn more about our editorial standards here.
💊 Ingredients of Prozac ®
✅ How to use Prozac ®
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Description of the active ingredients of the preparation Prozac ® (Prozac ® )
The scientific information provided is general and cannot be used to make decisions. decisions about the use of a particular drug.
Update date: 2020.06.09
Marketing authorization holder:
ELI LILLY VOSTOK, S.A. (Switzerland)
PATHEON FRANCE, S.A.S. (France)
ATX code: N06AB03 (Fluoxetine)
Active substance: fluoxetine (fluoxetine)
Rec.INN WHO registered
Release form, packaging and composition Prozac®
Capsules hard gelatin capsules, size #3, opaque, green/cream, imprinted with the LILLY logo and the identification code "3105"; the contents of the capsules are white powder.0008
Excipients : starch, dimethicone.
Composition of the capsule shell: patented blue dye (patent blue V dye), yellow iron oxide dye, titanium dioxide, gelatin, food ink (for identification printing).
14 pcs. - blisters (1) - packs of cardboard.
Clinical and pharmacological group: Antidepressant
Pharmacotherapeutic group: Antidepressant
Antidepressant, propylamine derivative. The mechanism of action is associated with selective blockade of neuronal reuptake of serotonin in the CNS. Fluoxetine is a weak antagonist of cholino-, adreno- and histamine receptors. Unlike most antidepressants, fluoxetine does not appear to cause a decrease in the functional activity of postsynaptic β-adrenergic receptors. Helps improve mood, reduces feelings of fear and tension, eliminates dysphoria. Does not cause sedation. When taken in average therapeutic doses, it practically does not affect the functions of the cardiovascular and other systems.
Absorbed from the gastrointestinal tract. Weakly metabolized during the "first pass" through the liver. Eating does not affect the degree of absorption, although it may slow down its rate. C max in plasma is achieved after 6-8 hours. C ss in plasma is achieved only after continuous administration for several weeks. Protein binding 94.5%. Easily penetrates through the BBB. It is metabolized in the liver by demethylation to form the main active metabolite of norfluoxetine.
T 1/2 fluoxetine is 2-3 days, norfluoxetine is 7-9 days. Excreted by the kidneys 80% and through the intestines - about 15%.
Indications of the active substances of the drug Prozac®
Depression of various origins, obsessive-compulsive disorders, bulimic neurosis.
Open list of ICD-10 codes
The method of administration and dosing regimen of a particular drug depends on its form of release and other factors. The optimal dosage regimen is determined by the doctor. Compliance of the dosage form of a particular drug with indications for use and dosing regimen should be strictly observed.
Initial dose - 20 mg 1 time / day in the morning; if necessary, the dose can be increased after 3-4 weeks. The frequency of admission is 2-3 times / day.
The maximum daily oral dose of for adults is 80 mg.
From the side of the central nervous system: possible anxiety, tremor, nervousness, drowsiness, headache, sleep disturbances.
From the digestive system: possible diarrhea, nausea.
From the side of metabolism: possible increased sweating, hypoglycemia, hyponatremia (especially in elderly patients and with hypovolemia).
From the reproductive system: decreased libido.
Allergic reactions: possible skin rash, itching.
Other: joint and muscle pain, shortness of breath, fever.
Contraindications for use
Glaucoma, bladder atony, severe renal dysfunction, benign prostatic hyperplasia, simultaneous administration of MAO inhibitors, convulsive syndrome of various origins, epilepsy, pregnancy, lactation, hypersensitivity to fluoxetine.
Use in pregnancy and lactation
Contraindicated in pregnancy and lactation.
Use in hepatic impairment
Use with extreme caution in patients with hepatic impairment.
Use in impaired renal function
Contraindicated in severe renal impairment. Use with extreme caution in patients with moderate and mild renal impairment.
Use in children
The safety of fluoxetine in children has not been established.
Use in elderly patients
Elderly patients require dosage adjustment.
Use with extreme caution in patients with impaired liver and kidney function, with a history of epileptic seizures, cardiovascular diseases.
In patients with diabetes mellitus, changes in blood glucose levels are possible, which requires correction of the dosing regimen of hypoglycemic drugs. When used in debilitated patients while taking fluoxetine, the likelihood of developing epileptic seizures increases.
With the simultaneous use of fluoxetine and electroconvulsive therapy, prolonged epileptic seizures may develop.
Fluoxetine can be used no earlier than 14 days after discontinuation of MAO inhibitors. The period after the abolition of fluoxetine before the start of therapy with MAO inhibitors should be at least 5 weeks.
Elderly patients require dosage adjustment.
The safety of fluoxetine in children has not been established.
Do not drink alcohol during treatment.
Influence on the ability to drive vehicles and mechanisms
During the period of treatment, one should refrain from potentially hazardous activities that require increased attention and rapid psychomotor reactions.
When used simultaneously with drugs that have a depressant effect on the central nervous system, with ethanol, a significant increase in the inhibitory effect on the central nervous system, as well as an increase in the likelihood of convulsions, is possible.
With simultaneous use with MAO inhibitors, furazolidone, procarbazine, tryptophan, serotonin syndrome may develop (confusion, hypomania, restlessness, agitation, convulsions, dysarthria, hypertensive crisis, chills, tremor, nausea, vomiting, diarrhea).
With simultaneous use, fluoxetine inhibits the metabolism of tricyclic and tetracyclic antidepressants, trazodone, carbamazepine, diazepam, metoprolol, terfenadine, phenytoin, which leads to an increase in their concentration in blood serum, an increase in their therapeutic and side effects.
With simultaneous use, inhibition of the biotransformation of drugs metabolized with the participation of the CYP2D6 isoenzyme is possible.
When used simultaneously with hypoglycemic agents, their effect may be enhanced.
There have been reports of increased effects of warfarin when co-administered with fluoxetine.
When used simultaneously with haloperidol, fluphenazine, maprotiline, metoclopramide, perphenazine, periciazine, pimozide, risperidone, sulpiride, trifluoperazine, cases of extrapyramidal symptoms and dystonia have been described; with dextromethorphan - a case of the development of hallucinations is described; with digoxin - a case of increasing the concentration of digoxin in the blood plasma.
When used simultaneously with lithium salts, an increase or decrease in the concentration of lithium in the blood plasma is possible.
With simultaneous use, it is possible to increase the concentration of imipramine or desipramine in the blood plasma by 2-10 times (may persist for 3 weeks after fluoxetine is discontinued).
When used simultaneously with propofol, a case is described in which spontaneous movements were observed; with phenylpropanolamine - a case is described in which dizziness, weight loss, hyperactivity were observed.
Co-administration may enhance the effects of flecainide, mexiletine, propafenone, thioridazine, zuclopenthixol.
How we are treated: Prozac. From depression to bulimia
16:00, December 14, 2017
Analysis of one of the popular antidepressants how it is customary to treat them and whether the antidepressant Prozac works, read in the new material of the heading "How we are treated."
Prozac is on the list of the most important, safest and most effective (including from an economic point of view) drugs according to the World Health Organization. However, as we remember after the article with the analysis of Tamiflu, this does not guarantee its effectiveness.
Prozac is prescribed for the treatment of depression, obsessive-compulsive disorders, bulimia nervosa. If you know very well what it is, you can immediately skip to the “from what, from what” part.
When life is not nice
Depression is called depression, loss of interest in what used to make the patient happy. According to the international classification of diseases ICD-10, the main criteria by which such a diagnosis can be made include depressed mood for more than two weeks, loss of strength and consistently high fatigue (more than a month) and anhedonia (the inability to enjoy what used to bring joy). Doctors consider additional criteria for depression to be pessimism, low self-esteem, thoughts of death and suicide, appetite disturbances (weight loss or overeating), sleep problems, constant fears and anxieties, feelings of worthlessness and guilt, inability to concentrate, and a constant sweet taste in the mouth. These symptoms are unlikely to occur simultaneously (for example, fatigue and apathy may predominate in some cases, while anxiety and guilt may prevail in others), therefore, in order to diagnose depression, the patient's condition must meet at least two main criteria and three additional ones. At the same time, according to the definition of the US National Institute of Mental Health, such a state should last quite a long time (more than two weeks).
Severe depression (clinical) includes a complex set of symptoms called major depressive disorder and may sometimes not be accompanied by low mood at all. However, because of her, the patient is physically unable to live and work normally, and the comments of those around him in the spirit of “he just can’t pull himself together” or “enough to turn sour that he spread snot” sound like a mockery. Such phrases stigmatize depression, blaming a person for his condition, while he himself will not be able to cope and needs treatment. To diagnose major depressive disorder, there is a whole questionnaire of major depression compiled by the World Health Organization. Also, depressive disorders include other conditions accompanied by depression, such as dysthymia (daily low mood and mild symptoms of depression for two years or more).
The causes of depression can be very different: somatic (due to diseases of the body), psychological (after strong dramatic experiences, such as the death of a relative) and iatrogenic (as a side effect of certain drugs). As strange as it would be to provide first aid to a victim of an electric shock without removing the wire from him, it is difficult to cure the symptoms of depression without eliminating its cause or changing the lifestyle that led the patient to such a state. If the patient lacks some essential substances (for example, tryptophan), it is important to make up for their lack, and not just fight the depressed mood with drugs. If he has some kind of psychological trauma, the help of a psychotherapist will be required. And for a person whose depression is provoked by hormonal disorders, neurological diseases, heart disease, diabetes, or even cancer (and this happens), it is more important to cure the disease itself, and symptomatic treatment of depression will be a secondary goal.
When you can't stop
Obsessive-compulsive disorder, or OCD (also called obsessive-compulsive disorder), consists of two mandatory components: obsessions (obsessive anxious or frightening thoughts) and compulsions (compulsive actions). A classic example is cleanliness-related OCD, where a person is afraid of contamination or contamination by microorganisms. Such thoughts and fears are called obsessions. In order to protect themselves from them, a person will worry too much about cleanliness, such as constantly washing their hands. Any contact with a non-sterile, according to the patient, object, plunges such a person into horror. And if you can’t wash your hands again, he will experience real suffering.
You can learn how to understand medicines on your own in the author's online course "How We Are Treated" by the editor of Indicator.Ru Ekaterina Mishchenko: https://clck.ru/Pnmtk
This "protective" behavior is called compulsion. The desire for cleanliness can be understood if a person is in conditions of complete unsanitary conditions or, on the contrary, wants to maintain sterile conditions somewhere in the operating room. But if the action loses its true meaning and becomes a mandatory ritual, it becomes a compulsion.
However, OCD can manifest itself not only as a fear of pollution, but also as excessive superstition, fear of losing a necessary object, sexual or religious obsessive thoughts and related actions. Their reasons may lie in several areas: biological and psychological. The first includes diseases and features of the nervous system, lack of neurotransmitters (biologically active substances that ensure the transmission of a nerve impulse from one neuron to another, for example, dopamine or serotonin), genetic predisposition (mutations in the hSERT gene encoding the serotonin carrier protein and located on 17 -th chromosome).
There is also an infectious theory of the development of OCD, associated with the fact that in children it sometimes occurs after infection with streptococcus. This theory is called PANDAS - an abbreviation for the English Pediatric Autoimmune Neuropsychiatric Disorders Associated with Streptococcal infections, which translates as "Children's autoimmune neuropsychiatric disorders associated with streptococcal infections. " The cause of this syndrome may be an attack of its own antibodies produced against streptococcus on the patient's nerve cells. However, this theory has not yet been confirmed.
Another group of explanations for the development of OCD is psychological. They go back to the theories of the beginning of the last century (from Freud to Pavlov). Mayakovsky's father died of blood poisoning after being injected with a binder, so it is believed that the poet also showed a pathological love for cleanliness. But you don't have to be a futurist poet to experience the full benefits of OCD: even dogs and cats suffer from it. Only in them this is expressed in the endless licking of wool and attempts to catch their tail.
The Yale-Brown scale is used to diagnose obsessive-compulsive disorder. In the fight against OCD, the method of psychological persuasion can be useful: patients are patiently explained that if they skip the “ritual” once, nothing terrible will happen. But drugs are also used in treatment.
When you are how you eat
Bulimia nervosa (third indication for Prozac) is a binge eating disorder. The main signs of bulimia are uncontrolled eating in large quantities, obsession with excess weight (calorie counting, attempts to induce vomiting after eating, fasting, use of laxatives), low self-esteem, low blood pressure. Other symptoms are sudden changes in body weight, kidney problems and dehydration, enlarged salivary glands, heartburn after eating, and inflammation of the esophagus. Due to provoking vomiting, hydrochloric acid from the stomach constantly enters the oral cavity of patients, which can lead to grinding of tooth enamel and ulcers on the mucous membrane. According to the DSM-5 classification of diseases, uncontrolled consumption of large amounts of food and the simultaneous use of various drastic measures for weight loss is the main criterion for diagnosing bulimia nervosa.
Video about bulimia on the educational medical resource Open Osmosis (USA)
The causes of bulimia can be either biological (incorrect levels of hormones or neurotransmitters, including serotonin) or social. The importance of the latter is highlighted, for example, in a high-profile study among teenage girls in Fiji, which showed a sharp increase in cases of intentional bowel cleansing for weight loss in just three years (from 1995 to 1998) after television appeared in the province. Perhaps the desire to be like models from the screens and covers really pushes for such behavior.
Bulimia can often be associated with other psychiatric disorders (depression, anxiety disorders, sleep disorders). According to a study by the New York State Psychiatric Institute and Columbia University, 70% of people with bulimia have ever experienced depression, compared with just over 25% in the general population.
Bulimia itself is not very common, and it can be more difficult to diagnose than the same anorexia, because changes in body weight in bulimia are less sharp and noticeable. For diagnosis, the food attitude test, developed by the Clark Institute of Psychiatry at the University of Toronto, and other tests based on it, are used. But (as with the tests for OCD and depression above), its result only indicates the likelihood that the patient has developed a disorder, but does not allow for a definitive diagnosis, especially for oneself.
From what, from what
What is a medicine that is prescribed for three types of disorders at once? The active ingredient in Prozac is fluoxetine. The patent for Prozac expired back in 2001, so many generics are available in pharmacies - cheaper copies that use the same active ingredient, but are not as well studied and may differ slightly from the original. These drugs include Fluoxetine, Prodel, Profluzak, Fluval.
Fluoxetine, discovered and marketed by Eli Lilly and Company, belongs to a group of antidepressants called selective serotonin reuptake inhibitors. This group is considered third-generation antidepressants, fairly well tolerated and without significant side effects.
Fluoxetine is readily absorbed into the blood, can bind to plasma proteins and accumulate in body tissues. It also penetrates the blood-brain barrier, which protects the nervous system and brain from many substances circulating in the blood. There, in the nervous system, it works in the synaptic cleft we have already mentioned, preventing the excess serotonin ejected from the synapse from returning to the neurotransmitter. Because of this, serotonin is longer present in the synaptic cleft and can bind to receptors. How exactly fluoxetine achieves this effect is not clear even to manufacturers, but it is known that it has little effect on the work of other neurotransmitters. However, at high doses, fluoxetine increases adrenaline and dopamine levels, as studies in rat brain tissue show.
Fluoxetine and its metabolite, norfluoxetine, can interfere with each other's actions. Because of this, according to scientists from the Institute of Research Medicine in Barcelona, a constant concentration of fluoxetine in the blood is achieved only after four weeks of taking the drug. Similarly, the effects of taking the medicine do not disappear immediately. Associated with this is the difficulty in selecting the required dose for a particular patient.
Serotonin itself, which is absolutely incorrectly called the “hormone of happiness” (hormones are produced in one organ of the body, but perform their function in another, serotonin in this context simply conducts nerve impulses in the parts of the brain responsible for good mood, and is produced there well), in fact, it performs much more functions. Yes, it affects mood, sleep, and appetite, so some cases of depression, bulimia nervosa, and OCD may be caused by insufficient production of this neurotransmitter and corrected with serotonin reuptake inhibitors. But in addition, platelets can actively capture it and affect blood clotting. Serotonin is also involved in the processes of memorization and learning. At the same time, not only vertebrate animals can produce it: according to a study by Chinese and American scientists, the pain from an insect bite is largely due to the presence of serotonin in the poison, and the dysentery amoeba, according to an article in Science, can cause diarrhea by releasing serotonin in our intestines.
The lists (not) included
But all these are only mechanisms, and besides, they have not been studied to the smallest detail. To understand how this works in real people and how often it helps, let's turn to clinical trials. However, anyone who enters the combination “fluoxetine depression double blind randomized controlled” into the PubMed scientific article database and filters clinical trial (clinical trial) will see more than 558 articles, up to work comparing the effectiveness of Prozac and homeopathy.
Double-blind, randomized, placebo-controlled method is a method of clinical drug research in which subjects are not privy to important details of the study being conducted. “Double-blind” means that neither the subjects nor the experimenters know who is being treated with what, “randomized” means that the distribution into groups is random, and placebo is used to show that the effect of the drug is not based on autosuggestion and that this medicine helps better than a tablet without active substance. This method prevents subjective distortion of the results. Sometimes the control group is given another drug with already proven efficacy, rather than a placebo, to show that the drug not only treats better than nothing, but also outperforms analogues.
No living person can analyze them within an adequate period of time. And even Cochrane reviews can be found as many as 36 (that's really a lot), although not all of them consider the action of fluoxetine for its direct indications (depression, bulimia and obsessive-compulsive disorder).
The Cochrane Library is a database of the Cochrane Collaboration, an international non-profit organization involved in the development of World Health Organization guidelines. The name of the organization comes from the name of its founder, the 20th-century Scottish medical scientist Archibald Cochrane, who championed the need for evidence-based medicine and the conduct of competent clinical trials and wrote the book Efficiency and Efficiency: Random Reflections on Public Health. Medical scientists and pharmacists consider the Cochrane Database one of the most authoritative sources of such information: the publications included in it have been selected according to the standards of evidence-based medicine and report the results of randomized, double-blind, placebo-controlled clinical trials.
One of them is dedicated to antidepressants used against bulimia nervosa. Although in general the authors note that there is little data on this topic, fluoxetine (for which there were only five randomized double-blind controlled trials in 2003) is recognized as a leader in this direction. However, the authors refuse to recommend this medicine in the conclusion, arguing that not all clinical trial data have been published and are available for consideration.
A 2008 review reviewing the benefits of serotonin reuptake inhibitors (including fluoxetine) in obsessive-compulsive disorder concluded that they worked better than placebo, and the side effects associated with them were much more significant, among which nausea was the most common. , insomnia and headache. According to a 2013 review, the usefulness of this same group of drugs in autism and related OCD is unclear, and the data are insufficient to conclude.
The most popular subject of fluoxetine reviews was fighting depression. But the authors of most of them note the lack of data (for example, in this 2013 review). In a review with broad inclusion criteria, where the effectiveness of fluoxetine against depression in adults was investigated in 1177 randomized controlled trials, the authors conclude that it is about as effective as other antidepressants, but less toxic. However, they warn against hasty decisions, since most of the studies were conducted on small groups of people (100 or less) and were funded by the manufacturer, which is more profitable to publish only positive results, hiding information about failures. Data on postpartum depression are also found to be insufficient and inconsistent. The same issues are highlighted by a review of articles on the effectiveness of antidepressants against dementia-related senile depression.
Indicator.Ru concludes: one of the best stimulant antidepressants is still not perfect
A large number of studies confirm the effectiveness of fluoxetine, a key component of Prozac. But part of the reviews of the Cochrane Collaboration note that not all trial data have been published by manufacturers. And this accusation is not an empty phrase: according to Eli Lilly's internal documents, manufacturers during trials often attributed suicide cases to worsening depression or overdosing on the drug.
As a result, following numerous reports of suicide by patients prescribed this drug, the US Food and Drug Administration (FDA) has issued a warning label to the drug's packaging.
This does not mean that the harm from the drug always outweighs its benefits, but such dishonest behavior of manufacturers does not allow us to assess the risks more accurately. Given the difficulty with the selection of an individual dose and the slow effect, adjusting the dosage is really not easy.
Prozac is also classified as a serotonin reuptake inhibitor, but if the cause of your condition is something else, you need to pay more attention to finding and eliminating them than fighting depression. As we wrote above, somatic diseases (for example, cirrhosis of the liver, cancer or diabetes), and even a lack of vitamins, can also cause depression. In addition, depression or another disorder may be the result of psychological trauma that will be difficult to deal with without psychotherapy.
All this suggests that the drug should be used under the supervision of a doctor (most likely, it will not be sold without a prescription), and that its action alone may not be enough for a complete recovery. And don't forget that serotonin is involved in many other processes in the body. Therefore, you should not use the drug in violation of the functions of the liver and kidneys, an increased risk of thrombosis, and not only during pregnancy and lactation. With manic states and suicidal moods, it is also better to abandon the drug.