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Prozac and Weight Gain: What Users Say

Weight gain: mentioned by 52 users (4.2%)

Based on user experiences from 1,239 Prozac reviews, the following table shows the most commonly mentioned side effects.

All user comments are moderated by Drugs.com. Each review is verified for relevance and screened for inappropriate content. Side effects are user-reported and not clinically verified.

anxiety 16.2%
insomnia 9.0%
nausea 7.3%
tiredness 6.9%
sexual dysfunction 6.9%
depression 6.0%
loss of appetite 5.9%
panic attacks 4.4%
weight gain 4.2%
headaches 4.0%

Reviews for Prozac

Commonly mentioned side effects
  • Man...
  • Taken for 1 to 2 years
  • March 7, 2019

For Anxiety and Stress "I have been taking Prozac for roughly a year. Before that, I was on Lexapro for a year but switched due to weight gain. Where do I begin? This pill has given me confidence, more social ease, allowed me to live my life more freely and openly and not panic at the slightest inconvenience. I can go with the flow. I'm more regular, I sleep better, it's as though I was missing something and this is it. An additional bonus I've found, which I can find no information on is that it has made my hair grow thicker, faster and fuller. I wonder if anyone else has experienced this?"

10 / 10
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186 Report
  • Ngu...
  • January 27, 2020

For Depression "Anyone gain weight from taking Prozac after a long run? I dare not start Prozac after reading from the internet that Prozac is likely to cause weight gain after 6 months of taking it. Is it true? Can someone share their experience with me?"

6 / 10
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151 Report
  • Jan...
  • Taken for 5 to 10 years
  • May 2, 2020

For Obsessive Compulsive Disorder "Fluoxetine helped me to get out of a bad place with regards to my OCD. I'm so thankful for it. Compared to other medications that I've taken in the past, it has very few side effects, especially in terms of weight gain, etc. Alongside therapy, it has changed my life. Without even realizing it, my compulsions and ruminating lessened dramatically. It's worth going through the first three weeks of transition to experience the final effects."

10 / 10
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102 Report

Frequently asked questions

  • ber...
  • Taken for 1 to 2 years
  • December 2, 2015

For Anxiety and Stress "I went on Prozac about a year ago after I saw how well it helped my boyfriend. We met two years ago, and I knew he was suffering, but didn't know from what. He and I were soon diagnosed with OCD. I was so wary of taking any meds, especially any that said 'weight gain' as a side effect because of my obsessive-compulsive behavior with my appearance. One day, my boyfriend said, 'It's okay if you gain a couple, if anything, you need to,' said in the nicest way. So I finally gave in and started at 10 mg. I later went up to 20 mg, and I noticed I didn't seem to be beating myself up every day, maybe only every few days. I didn't gain any weight, and it even helped with my binge eating disorder. It also helped my more 'intense' feelings to 'normal'."

9 / 10
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120 Report
  • Luk...
  • Taken for 2 to 5 years
  • July 14, 2019

For Depression "I’ve been taking Prozac for 2 1/2 years now. I started in September 2017 at 20mg, stopped in October 2018, and restarted in January 2019 at 10mg. As of July 2019, I’ve increased to 20mg. Prozac makes me feel “normal” every time, especially the 20mg. It’s amazing! What’s odd is the first time I took it, I gained weight and lost sexual function; however, this time I seem to be losing weight and sex isn’t impaired. I wonder if stopping and taking it again changes how the body responds? Overall 10/10."

10 / 10
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86 Report

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  • Ziz...
  • Taken for 1 to 6 months
  • February 4, 2013

For Depression "I am a 25-year-old PhD student. I have been taking Prozac for 5 weeks now. It started affecting me on the 3rd week. I felt so much more active, and I had hope for living. I am working more efficiently, and my sleep schedule is perfect. I am gaining some weight, which means I should also start exercising. I still have vivid dreams and wake up several times during the night, but I don't mind it because my life has changed so much, and I feel so happy after years of depression."

8 / 10
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  • LWH...
  • Taken for 6 months to 1 year
  • January 5, 2020

For Depression "I've taken this medication Prozac for about 7 months. I had a little nausea, weight gain, sleeping more, and felt like less energy, but for once I was content and happy. I dealt with the loss of a child and the father of my kids at 22. I never sought out help or treatment until last year. I finally drew a line with my depression and anger. Felt like a crappy parent. This medication has had its side effects. My biggest notice was my sexual desire was 100% no longer. I had tried dating but had no desire to talk, touch, or be intimate. When I was having sex, it was somewhat uncomfortable and had a hard time with lubrication. I also found it hard to climax. I read up and this is a side effect with fluoxetine. I didn't care though. For once I was happy and enjoyed my life. It is not for everyone."

8 / 10
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More FAQ

  • Emm...
  • May 1, 2016

For Depression "I have had depression and anxiety for several years, and have been on many antidepressants and none have been as effective as Prozac has been for me. I was previously on Celexa, and although it did help my depression, it also made me gain a lot of weight. Since being on Prozac, though, my appetite has gone down tremendously, and I feel amazing. I have never been this happy even before depression hit me."

10 / 10
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83 Report
  • bet...
  • Taken for 1 to 6 months
  • September 9, 2018

For Anxiety and Stress "I started taking Prozac 3 months ago for anxiety. I started with 2.5 mg for two weeks, then 5 mg for two weeks, then 10 mg for two weeks, and finally my dose of 20 mg. I think this really helped mitigate possible side effects. I haven’t experienced any insomnia or weight gain, or any of the other side effects I read about before starting this medication. Prozac has worked wonders for me, and it’s honestly like my happy pill. It has rid me of the intrusive, anxious thought patterns and panic attacks, and I feel like a more reasonable and stable person. I still get anxious every day, but I just feel a lot more in control of myself and my state of mind, and my self-talk is more effective than it used to be. I definitely recommend Prozac for anyone suffering from anxiety and panic attacks!!"

9 / 10
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66 Report
  • PTS...
  • November 2, 2016

For Depression "Six years ago, I almost lost my life from an abusive relationship. I am 24 years old now. Luckily, I am a survivor of domestic violence. From that traumatic time in my life, I have been severely depressed, anxious, and have had thoughts of suicide. For the past six years, I have been on and off depression medications. Some have worked, but the effects were too extreme. I tried Effexor but didn't like it too much, and the withdrawal was terrible. Then I tried to work things out without medication and was doing well for a while but became very depressed and gained weight, so I decided to give medications a try again. Recently, I started on Prozac (10 mg) about a week ago. So far, the low dose is good for me. I am more positive, exercise daily, and follow a new diet."

9 / 10
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70 Report
  • sea...
  • March 22, 2018

For Obsessive Compulsive Disorder "I was only given Prozac for my OCD because bipolar meds and antidepressants can be a nightmare. Prozac is my life now. I've been on it for years. I tried Trintellix to see if it was better, and that experience scared me. Prozac is so far the best for me. Amazing because it is so old. But it literally saved my life. I had to try lots of other SSRIs before Prozac. Prozac took a long time to kick in, but all good things are worth the wait. I was definitely crawling before I walked again. I just want to say that I'm so happy Prozac was invented. It made me feel normal again. It's given me myself back. It didn't change me or numb me, it made me feel alive. I owe all my progress to Prozac in terms of OCD. I was on the verge of ECT. I don't have any side effects except some weight gain (I was so skinny before) and being tired when night comes (I take it at night). Prozac is one of the best things that happened to me in life, and I can't wait to take it tonight."

10 / 10
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  • Anonymous
  • October 30, 2008

For Premenstrual Dysphoric Disorder "After about 3 months or so, all of the side effects that I was having disappeared. It works great for my PMS, anxiety, and even helps me think clearer (ADD). Just be patient. One thing that I don't like is the weight gain, but plump and happy is better than thin and cranky."

9 / 10
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102 Report
  • mus...
  • March 26, 2013

For Depression "I was on Prozac for 6 weeks, and it made me gain weight and feel numb and apathetic about every aspect of my life. I stopped caring about my work performance, stopped wanting to see friends, had low energy yet trouble falling asleep, and had no sex drive whatsoever. The side effects were more depressing than my life was before."

1 / 10
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85 Report
  • Anonymous
  • Taken for less than 1 month
  • August 1, 2012

For Depression "Started taking this a week ago for moderate depression and anxiety. I've been on Zoloft and Paxil before, but the Zoloft made me exhausted and the Paxil made me gain weight, and missing doses caused 'brain zaps' like mini electric bolts. I felt better the very first day, and I knew the exact moment it came on. Even a coworker noticed my smile was like nothing before. Every day thereafter, my mood has been amazing. My doctor told me to start with 10mg, and then 20mg after a week, but I jumped right into the 20mg because I know my tolerance for medicines. I still have some social anxiety, so he may bump me to 30mg next visit, but right now even at this dosage I feel like life is worth living and is manageable."

10 / 10
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70 Report
  • Mrs...
  • Taken for 1 to 2 years
  • January 13, 2019

For Obsessive Compulsive Disorder "I’ve been taking Prozac for 1 year now. I started with 20 mg. The anxiety and obsessive thoughts were still there. My doctor decided I should go up in the dosage to 40 mg. And it helped tremendously. I would say the side effects while being on the medicine were weight gain and inability to orgasm. After 8 months of being on 40 mg, she suggested trying 30 mg, and that was definitely a game changer. I am now able to reach orgasm normally. The first three weeks, my sleep was still disrupted, so she prescribed me trazodone 25 mg. I took that for the first two months, and it helped me. I don’t need it anymore."

10 / 10
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39 Report
  • eis...
  • Taken for 2 to 5 years
  • February 19, 2020

For Major Depressive Disorder "While it did help my depression, it made me gain 30 lbs and made me a walking zombie. I was unable to feel emotion, just a numb feeling. My husband commented after I stopped taking it how much easier it was to talk to me. He said while I was on it I would look at him with a blank stare while he was talking and not really reply or just ignore him altogether. I was in my own little world on this stuff. Libido suffered immensely as well."

1 / 10
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41 Report
  • Anonymous
  • February 9, 2011

For Anxiety and Stress "I have been on Prozac since I was 18. I had huge depression, anxiety, OCD, and PTSD problems. I was so anxious I couldn't even take the pill for the first month because I thought it was going to kill me! Seven years later, I am a different person. I now have a partner and child - before this would have been impossible. I can also deal with stress much better, and my rage and anger have also calmed down. The only downside to this medicine is the weight gain. I have gained 4 stones due to Prozac, but I would rather be overweight than suicidal and unable to cope with life."

8 / 10
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71 Report
  • Ash...
  • October 2, 2017

For Depression "I was going through a very deep and dark depression for several months. Prozac was the only antidepressant to work for me. After about 2 weeks, I could tell the medication was really working. I wasn't having constant OCD-related circling thoughts that made my depression worse, and I wasn't on the verge of crying every second. This pill is a miracle for me. No side effects, maybe weight gain, but I'm also eating again when before I was barely eating and dropped 10 lbs. Definitely take the medication at night because it'll make you tired if you take it in the morning."

10 / 10
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46 Report
  • Sou...
  • Taken for 1 to 2 years
  • July 2, 2016

For Obsessive Compulsive Disorder "If you scroll down a bit to 2014, you will find my rave review of Prozac for OCD, and more than 100 people found it useful as well, which is great. Now it's 2016, a year and a half later, and I went from 115 lbs (I NEVER struggled with weight) to 151 lbs today, and I'm just 5'2'. My diet did NOT change. In fact, I battled anorexia in my teens. I just don't enjoy food that much and still don't. I truly believe some people may eat more, but ultimately it messes with your thyroid and hormones badly. So, this is what I'll say: Prozac is pure genius and DOES work very, very well. You will probably lose weight in the first few months, and then, as you approach a year, the weight comes on fast and hard."

10 / 10
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53 Report
  • Nel...
  • Taken for 1 to 2 years
  • May 30, 2020

For Anxiety and Stress "I had anxiety since I was a child. I remember having my first panic attack when I was playing with my siblings, not knowing what it was. Years later, I got diagnosed with Generalized Anxiety Disorder. After I couldn't bear my anxiety anymore and it started to affect my profession, I started taking Prozac 20mg in October 2018. The first two months, I experienced a terrible loss of appetite and weight loss, subsequently. Also, very heavy menstruation for months, then it went back to a normal flow. Vivid dreams were frequent, too, not anymore, though. After almost two years of use, I have gained at least 25 lbs, which is frustrating for me. In terms of anxiety, I do think that this drug controlled at least 85% of my anxiety and panic attacks. My anxiety now is very occasional, and when I have it, it either goes away by itself or stays with me the whole day, regardless of my relaxation practices."

8 / 10
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29 Report
  • Anonymous
  • February 3, 2017

For Anxiety and Stress "Prozac (10 mg) worked great for my depressive symptoms. I had energy and was motivated. I had no issues with weight gain or my sex drive. It did, however, significantly increase my anxiety. I had scary obsessive, intrusive thoughts, along with bad episodes of panic that came out of nowhere. I was scared to drive, go over bridges-there was always this fear of 'what if?' Everything that I could be anxious about, I was. I had a very difficult time quieting my mind, and at times I thought I was going crazy. Very scary experience overall. For those suffering from depression, I'm sure this RX is a godsend, but much too 'speedy' for my body."

4 / 10
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45 Report
  • lir...
  • January 5, 2014

For Anxiety and Stress "I started to take Prozac several months back to get off Effexor. It really made that transition smooth. I take 20 mg every other day. I find it helps with anxiety, but not enough to wean off Klonopin. I know I'm normally oversocial, and Prozac makes me antisocial. I don't mind because I'm only antisocial with people I don't need to be associated with. I believe my ability to orgasm has improved from Effexor to Prozac. I tend to sleep more than I should, but it's better than tossing and turning. My motivation is at an all-time low right now, I don't know if it's the Prozac or work. I gained weight initially, but it's coming off slowly and evening out. I would recommend Prozac, it's not as feeling/responsibility numbing as other meds."

8 / 10
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62 Report
  • Soo...
  • Taken for less than 1 month
  • June 26, 2017

For Panic Disorder "This is my second time taking Prozac. I took it for two years before for panic attacks, insomnia, OCD, and it did wonders. After a month, my head cleared up, my memory improved, as well as my sleep. (No longer waking up in the middle of the night worried about things.) Only downside is that I tend to gain a lot of weight on it. As soon as I stopped last time, the weight came off almost immediately. I plan to watch what I eat and exercise more this time. After a month now, I have already started to feel 2000% better and sleeping so good."

10 / 10
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37 Report
  • Vai...
  • Taken for 10 years or more
  • September 25, 2017

For Major Depressive Disorder "I have been on Prozac (fluoxetine) since 2000. I started with 20 mg, then 40 mg, and now 60 mg. I am also taking Navalpro 300 mg, twice a day. Prozac is the only medication that has made me function as a 'normal' person after being correctly diagnosed as having major depression. When I first desperately looked for help, my anxiety was unbearable. Prozac killed two birds with one stone-depression and anxiety. I had a rollercoaster journey, being prescribed other antidepressants together with Prozac. I have come to accept that the benefits outweigh the side effects. However, weight gain I have not accepted and am trying my best to watch calories and move around more often."

7 / 10
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35 Report
  • Hv5...
  • Taken for 1 to 6 months
  • June 17, 2014

For Depression "I've been on Prozac for just about 3 months. At first, I did not notice a difference for about a month, then I started feeling more energized for a few weeks. However, the weight is going on as fast as grass grows. I'm seeing my doctor today and need to switch. I've even been working out, walking, and have been more active. The weight gain is awful, at least for me."

4 / 10
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57 Report

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Reviews may be edited to correct grammar/spelling or remove inappropriate content. Reviews appearing to come from parties with a vested interest are not published. This information is not intended to endorse any medication and should not replace the expertise and judgment of healthcare professionals.