Paxil, Prozac, Zoloft Weight Gain



Are you taking or considering taking an SSRI antidepressant like Paxil, Prozac or Zoloft – and are you worried about the potential for weight gain?

The bad news is that you have reason to worry.  The good news is that most of the weight gain takes place over time, and that it doesn’t necessarily happen that often.

Let’s go through the details.

And for some useful ideas on how to fight weight gain, see The Top 10 Ways to Lose Weight.

The SSRIs and Weight Gain

First, you should know that weight gain is a possible and common side effect from antidepressants.  But how common is it?

An article on WebMD puts the incidence of weight gain on SSRI antidepressants in general as high as 25%.  That means that one out of four people taking them will gain weight.

Yikes!   Fortunately, the article also says that the weight gain may occur over use for more than 6 months.

That it takes some time for the weight to develop might explain why some studies have not shown it to be an issue.  A study that runs for just a month might not catch any weight gain, especially since it takes a while to develop.

So you can gain weight from antidepressants.  The confusing part?  You can also lose weight from them.  What’s it all mean?

It’s hard to say.  Scientific research is very limited into the side effects of a medication.  This makes it quite hard to figure out how common weight gain from SSRIs is and how much weight occurs in general.

On the one hand, you anecdotally hear about it all the time.  On the other, it is very hard to find actual scientific analysis of the issue.

Zoloft weight gain

Plugging the search phrase “Zoloft weight gain” (or rather the technical phrase “sertraline weight gain”) into a medical research database shows only 42 results, and very few of those actually discuss the issue.  This is despite millions of people taking that medication.

Prozac weight gain

Things look better for “Prozac weight gain” (166 results), but many of those results are dealing with a combination of Prozac and Zyprexa, not Prozac alone.

Paxil weight gain

Searching for “Paxil weight gain” finds only 71 results, and the vast majority of them have nothing to do with the subject directly.

Issues with the scientific research?

It is possible that the possibility of weight gain from antidepressants is overlooked due to how research is conducted.

We looked at a major analysis that was, on the surface, dedicated to finding the side effects from Zoloft.  Yet we searched through it and could not find a single time the word “weight,” meaning it completely missed both the possibility of weight gain and weight loss.

If other research studies similarly ignore the possibility of weight gain or loss, it is likely that it will be overlooked.

Still, we found some hints of data that may clarify the issue.

Side effect database

We ran Zoloft, Paxil and Prozac through a medical database dedicated to reporting of side effects.

Zoloft: No numbers on weight gain, but weight loss is a reported side effect

Paxil: No numbers on weight gain, but up to 1% report weight loss

Prozac: No numbers on weight gain, but up to 3% report weight loss

It’s somewhat odd that there are numbers reported for weight loss from antidepressants while weight gain, which is likely much more common, has no numbers directly associated with it – that we could find.

Next, we looked at an analysis of 700 patient reports.  The reports were generated on a site that allows patients to report side effects from medications.  Of those 700 reports, 49 said that weight gain was a side effect.  That’s about a 7% rate of weight gain.

One clinical study of several hundred people with major depression indicated that Paxil was associated with significant weight increase, Prozac with a modest, not-significant weight loss, and Zoloft with a minor and not significant weight gain.

Is Prozac or Zoloft more effective?

You may be confused because you don’t know what the differences between Prozac and Zoloft are.  For a head to head comparison of them, see here.

Related Articles:

  1. Why am I Depressed?
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  3. The Top 5 Songs About Depression
  4. The 14 Weirdest Medical Fact

15 thoughts on “Paxil, Prozac, Zoloft Weight Gain

  1. I am wondering what would cause the weight gain on Zoloft or other SSRIs? Someone close to me just started taking it and was experiencing nausea as a frequent side effect. Carbs were the only thing that would settle his stomach, so he was eating more carbs. Stuff like that can cause weight gain. Fortunately, the nausea seems to have mostly dissipated at this point, after two weeks of so of taking Zoloft.
    A couple of years ago I went on a drug that did NOT list weight gain as a side effect but it made me feel so sick that I also overate carbs to compensate and gained a bunch of weight.
    Or is it like the energizer bunny commenter above who said she gained and doesn’t eat much, so maybe it’s a metabolism thing that is independent of eating habits?
    I mean.. depression itself can cause some people to overeat and some people to lose their appetite. 
    Some people with IBS who haven’t been able to eat much may be taking zoloft for the offlabel benefit of settling their irritable bowels down, and may feel safer eating more and going out more to eat.
    I can also imagine a person who isolated as a result of their depression going out and socializing and therefore eating more. I really wish we had more info about what would be the cause of the weight gain (or loss in some cases.) Is it a change in habits or just an independent metabolic side effect?

  2. I’ve put on 14 lbs over a period of a year and a half, since i’ve been taking Sertraline after a major depression. I started on 200mg and gradually reduced to 50mg. In the beginning my appetite came back with a vengeance, and I wasn’t worried about about putting on weight cause I had lost so much when depressed. I have a sweet tooth too, and have been enjoying eating, but lately am making a determined effort to cut out sweets (not fruit). My knees are hurting when I walk (arthritis) so I must lose the weight. I exercise regularly but this doesn’t change the weight. In my case Sertraline seems to increase my appetite, which can extend to bingeing late at night!

  3. I took Prozac and it made me lose wight.
    I recently started it again and I find it very easy to avoid those daily temptations to overeat or eat the wrong things.I feel full with just a couple of bites ! But it does have a few side effects , granted everyone is different but I have trouble sleeping ,get hot flashes and feel a bit numb .When I’m on it , it’s hard to feel pure excitement .Other than that , it makes me overall a better person .

  4. I have “always” been thin, 5’9 never weighed more than 125-130, never owned scales and while I don’t eat large quantities and I’m fairly picky, I don’t always eat the healthiest. i.e. Cereal for dinner. I was blessed with some very good genetics and have NEVER been on a diet. I started talking 25 mg of Zoloft for Peri-menopause and also because of a lot of changes in my life within 6 months (moved, married, job change, sold my home, bought another home, daughter marrying, son graduating) Probably a miracle it was hooked up intravenously..However I have always been very active my entire life either running, biking etc…so that was my drug of choice (endorphin’s) I didn’t notice much change at all in my weight initially, then a year later my clothes size went from size 4 to an 8. 10-12 lbs doesn’t sound like a lot, but on someone that is on the slim side to begin with, made a big difference in my clothing and the way I felt. I was working out harder and eating less, which to be honest, much less and I would have been starving myself. I don’t sit around and my husband compares me to the Energizer Bunny. I decided after researching the weight gain to end the use of Zoloft and deal with the smaller issues in Menopause. 6 Months later, a bit more moody, but have lost ever pound I put on. I must have been the small percentage of people that had weight gain, but also I believe the studies don’t track the data long enough because it wasn’t immediate with myself. People keep saying the weight gain was Menopause and for a while I believed it until I decided to go off Zoloft and see what happened. Family history on my Mother’s side was that we all stayed slim even through the Menopause. So now when I get upset or moody, I put my running shoes on and hit the asphalt.

  5. I have only been taking zoloft now for a few months and even at a low dose 25mg! and man have I noticed the weight gain. I started this medicine around 190lbs (I am a 6ft tall average to large fram male that is 24 for reference) and in just this short period of time I have sky rocketed up to 205lbs keeping nearly the same diet and exercising as much or more as I did before. Today I stopped this medicine as the feeling of having tight clothing and not feeling happy about my self image outweighs the moderate benifits of taking it, we will see how things go.

  6. I found that slightly decreasing my dose over time allowed me to lose the weight I gained on Zoloft. I was only on 50 mg and went down to 25 mg. At 200 mg a day, you will probably have to talk with your doctor to see if you can slowly decrease your dose. Also, changing to a different SSRI may help. I’ve heard that some may be less likely to cause weight gain. Also, get out and exercise…dance, walk and just stay active. That helps me deal with my anxiety and helps me to control my weight.

  7. I have been taking Zoloft to treat chronic depression for 10 years. I take 200 mg a day. And, yes, I have had significant weight gain with Zoloft. I started out at about 130. I now weight about 162. Some of it may be due to having gone thru menopause, but I do believe that Zoloft is to blame for most of it. It would be nice to go off the Zoloft and see if that would help my weight issues, but unfortunately that is not an option for me. If anyone has had success in losing their Zoloft weight, I would love to know how they did it.

  8. How can they say that the majority of search results for “Paxil weight gain” have nothing to do with the subject directly? All I can find is one horror story after another about weight gain with Paxil! I feel absolutely convinced that Paxil can directly cause significant weight gain. I believe not only in Paxil’s causing weight gain, but in the inability to lose the weight while on Paxil! I also believe that many doctors and organizations do not want to believe that Paxil can cause weight gain. But I think that, as long as the weight gain is not significant, the benefits can “out-weigh” the risks.

  9. I think this website is most likely sponsored by the pharmaceutical industry. There is amply research out their to indiciate that WEIGHT GAIN is a side effect of SSRI’s. I’m sure my comment will be magically removed. Bev, MSN, ANP-BC

    1. We allow all comments – positive and negative. We do not delete comments that are intended to help readers. However, right off the bat, I can tell you that we have no affiliation to any company and do not promote their products within our content.

      Our aim is to provide well written and interesting content that explains medical issues so anyone can understand them, and always try to be impartial. Then to be a medical watchdog, reporting on the benefits and risks of medical issues, finding things that others overlook. Finally, to develop comprehensive coverage of medical topics. Currently, we are focused on analysis of new medications.

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  10. I gained 25 pound on Zoloft. I belive there is substanital evidence at this point to indicate tha the SSRI’s definatley can call significant weight gain. It is no longer up for debate!!!

  11. I lost weight when I started taking Paxil. Weird? I guess I don’t know anyone else who takes Paxil, so I thought weight loss was normal. Don’t start taking it! It has been impossible for me to get off it! For my needs it works, but there are side effects. I have come to the conclusion I am “good”, with fewer side effects, on a very low dose (5 mgrms). Probably have to take it forever.

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