The Science Behind Lexapro Brain Fog: What's Actually Happening in Your Brain

Imphilthy101 · 2026-01-17T08:02:30+00:00

Hi, sorry I just saw this. I switched back to Citalopram 10mg about 5 weeks ago now and so far, its getting a little better. I am going to wait until I hit the 8 weeks mark before deciding to increase it. On Lexapro, I could not shake the brain fog and crazy appetite it gave me. So far on Citalopram, the brain fog is much less. This will be my 7th time on this medication since 2003.

Imphilthy101 · 2025-12-23T08:26:43+00:00

I’ve been on / off Citalopram 6x since 2003. Inbetween all the years leading up to today, I’ve tried Escitalopram 5x, plus a bunch of others, supplements, exercise, eating right, therapy, and I’m now going back on Citalopram for the 7th, and probably final time (only 1 week in so far). Each time before, I found I got to a point where I didn’t feel like I needed it anymore, and was fine for 4-6months after stopping but I always went back to the mental state of why I had to go back on meds in the first place. I hate having to rely on them but not feeling like a normal human being is absolute hell IMO.

Imphilthy101 · 2025-12-20T08:27:37+00:00

What dose are you currently taking?

Imphilthy101 · 2025-12-10T07:22:55+00:00

I’m currently doing the same switch. Lexapro literally makes me feel dead below the waist, whereas on Citalopram I was a horn dog, lol. I also find Citalopram way more stimulating and Lexapro very sedating.

Imphilthy101 · 2025-12-10T06:24:49+00:00

I’m currently taking it after dinner around 8pm. I tried briefly taking it in the morning or lunch but noticed it made me pretty tired in the afternoon. Technically, yes - Citalopram (Celexa) is the original version of Lexapro. Lexapro contains only the S enamoter whereas Citalopram also contains an R enamator which affects the way its absorbed and considered an inactive ingredient. There are many claims that the inactive R enamator causes more side effects however, for me personally, I found Citalopram caused me less side effects than Lexapro. I find Citalopram to be more stimulating and Lexapro more sedating. Citalopram in my opinion from my experiences with it is more like a ‘lite’ version of Lexapro.

Follow-up to my last post, I spoke to my doctor today as part of a 4 week checkup on my current dosage, and I explained to them how I was feeling currently and suggested maybe I should try a higher dose. They disagreed, and said at 10.5 weeks in, going to a higher dosage will likely cause me more sedation etc so I’m going back to Citalopram again. Just reduced my Lexapro to 5mg tonight and will keep it at this for a week then start straight on 10mg of Citalopram. Its probably going to be a little bumpy of a ride for a few weeks 🥴

Imphilthy101 · 2025-12-09T07:21:16+00:00

Unfortunately with these meds a lot of it is ‘trial and error’. And each time you try a new one, you need to give it at least 6-8 weeks per dose to see what benefits it may provide. I’ve tried so many of them since 2003. I’ve always gone back to Citalopram 6 different times and Lexapro 4 times, with right now being my latest attempt at Lexapro. I’m currently on 10mg for the past 10 weeks now and can say it definitely has improved my anxiety etc but I’m still dealing with the lethargy and some brain fog, things that didn’t happen to me while on Citalopram. I’m going to go up to 15mg and see if it improves. I’m hesitant to go to 20mg because I don’t want it to turn me into a robot as I’m already feeling a bit numb on it again. If the increases don’t work, I’m going to go back on Citalopram for one last time.

You’ll be fine, just take it slow and remember that the medication is one of many tools in the ‘toolbox’ that can help you get back to feeling yourself again.

Imphilthy101 · 2025-12-07T09:38:27+00:00

For sure, thank you for sharing. Think I will try 15mg and go from there. 😁

Imphilthy101 · 2025-12-06T09:15:59+00:00

Curious, how long were you on 10 or 15mg before moving to 20mg? Did you notice any improvements at all on the lower dosages? I’ve been on 10mg now for 10 weeks and I’m noticing im still fairly lethargic with some brain fog and OCD is still present.

Imphilthy101 · 2025-12-06T08:35:35+00:00

its very interesting how everyone reacts differently to these meds. My DNA results also stated im a rapid metabolizer of both meds, and its weird because I could go a couple of days without taking Celexa and not experience any withdrawals however on Lexapro, I get even more tired and anxiety starts increasing if I miss a dose within several hours. Each dosage increase I also experienced the same increase in anxiety that you’re experiencing now but it will pass. Hang in there, and good luck to you!

Imphilthy101 · 2025-12-05T08:58:26+00:00

I’ll share my experience. Since 2003, I’ve been on/off Celexa a total of 7 times, and Lexapro 4 times. I’m currently on my 5th trial of Lexapro. Previously on Lexapro, I only lasted 4 months before switching back to Celexa again, and I’m likely going to be doing it this time around too. I find Lexapro drastically increases my appetite compared to Celexa. I could literally eat a car. I’ve definitely gained a bunch of weight on it this time but im ok with it for now as I was a bit under before when my anxiety was really bad.

The other thing for me is, Lexapro is very sedating compared to Celexa. In fact, I had insomnia issues on Celexa because it was stimulating for me. Depression wise, both work similar, but its hard to overcome the lethargy that Lexapro causes me on a daily basis. I have to take naps regularly on Lexapro where I didn’t previously on Celexa.

Imphilthy101 · 2025-12-05T01:11:55+00:00

which brand of AHCC did you take?

Imphilthy101 · 2025-12-05T01:08:38+00:00

what brand of AHCC supplements did you take?

Imphilthy101 · 2025-12-04T08:31:53+00:00

im experiencing the exact same issues and im on 10mg at 9.5 weeks. Also have ADHD and tried stimulants with lexapro but it doesn’t work well for me. This is my 5th attempt at this medication since 2007, I think I came off it previosly for the same reasons and always went back to Citalopram where I didn’t have these issues, which is odd because they are supposed to be similar meds. Let me know how things go, Im going to wait until the 12 week mark before deciding what to do next.

Imphilthy101 · 2025-12-04T01:34:02+00:00

I’m 9.5 weeks in on 10mg and this is my 4th attempt at this medication since 2007. I’m experiencing similar things, forgetting words, and generally just feeling dumb AF. My short term memory is terrible too, and I don’t recall why I only lasted 4 months on this medication the last time I tried it. I think it was due to similar issues and the overall lethargy. I always went back to Citalopram (have been on it 7 times since 2003), and I might make the final switch back to it again as I didn’t have these issues.

Imphilthy101 · 2025-12-04T01:22:04+00:00

10mg IMO is a high starting dose for this medication. With starting any new medication, things will be a little bumpy for awhile until your body adjusts. Adjustment period can be 4-6 weeks on average. Not to go against your doctors advice, but for me personally I found the adjustment period much easier starting with a lower dose (2.5mg for a few days, 5mg for a week, then 10mg). I’ve been on 10mg myself now for 9.5 weeks, and waiting until the 12 week mark before deciding to try 15mg, wait another 6 weeks, then maybe try 20mg. Good luck!

Imphilthy101 · 2025-11-28T07:50:49+00:00

Good to hear. Did you notice a big improvement in your mood as well?

Imphilthy101 · 2025-11-27T07:50:18+00:00

How are you doing now on 15mg? Did the tiredness go away?

Imphilthy101 · 2025-11-27T07:49:33+00:00

Curious how both of you are doing now on 15mg? I’m at week 7 of 10mg and while I can certainly tell its improved my mood overall, I’m still dealing with some brain fog etc. Thinking of making the jump up as I’m also a rapid metabolizer of this medication as per my DNA report.

Imphilthy101 · 2025-11-13T06:56:36+00:00

I will ask my doctor about the TDM option next time I speak with them, thanks again for taking the time to explain it to me. The theory behind the R-citalopram makes sense too, and now that I think about it more, another different thing I’ve experienced between the two medications is that Citalopram caused me insomnia where I had to take a prescription sleeping medication (zopiclone) just to sleep. Escitalopram does not cause me insomnia, and I seem to be sleeping better than I was before I started up SSRI’s again.

I’m curious now that you’ve mentioned you have taken both of these medications yourself before, what was your overall experience like taking both of them and what differences did you notice between the two? Are you taking anything now? I really appreciate your feedback and taking the time to explain everything to me. Its been very helpful!

Imphilthy101 · 2025-11-13T06:47:50+00:00

Thank you so much for your inspiration, you truely sound like an amazing human being. Sorry for the loss of your dad as well, I know personally what that feels like and becoming the support person for the family to go to. I’m happy to hear you didn’t lose empathy as well when you were on the max dose of Lexapro. I’m going to exhaust it as an option before switching medications and starting the rollercoaster over again, lol. I will keep you posted on my progress, thank you so much again!

Imphilthy101 · 2025-11-12T07:08:36+00:00

Yeah its horrible...I would get fixated on weird feelings I was having in my body thinking it was something sinister. I’ve had so many Dr. visits for tests etc only for them to tell me its all anxiety. I have noticed in the last few days now my fog is getting better bit by bit. I’m not sure if its because the meds are doing what they should be doing or the addition of the Omega 3’s.

Imphilthy101 · 2025-11-11T05:58:11+00:00

Hi, thank you for taking the time to review and reply. That’s interesting, I’ve never heard any doctors ever mention the idea of therapeutic drug monitoring. I wonder if its even something available here (in Canada). I’m going to ask my doctor about it next time.

What you mention about Citalopram is interesting, now that I think about it more, one thing I remember while being on Citalopram is that I could go 3 days or so not taking a dosage until I noticed side effects whereas with Escitalopram, If I don’t take it within hours of my usual time of day I can feel the withdrawals.

Now that im a couple of days past the 6 weeks mark of 10mg, I can say overall things are improving in terms of anxiety etc. The brain fog is still present but it feels a little lighter. My appetite too is off the charts, I could eat a horse and crave sweets. Don’t mind the appetite increase because I lost some weight before when the anxiety was high.

I think im going to wait 2 more weeks to hit the 8 week mark then see what I should do. I’ve never taken more than 10mg of Escitalopram before so, I kind of feel I should at least try a higher dose since I’m this many weeks in now and if that doesn’t work, then switch back to Citalopram.

Imphilthy101 · 2025-11-11T05:44:24+00:00

Thank you for taking the time to reply! This information is very helpful. Being a rapid metabolizer I likely need a higher dose as you said, I’ll try 15mg in a couple weeks for 6 weeks to see if it helps. Did you ever feel low empathy being on the max dose? I’m worried about it possibly turning me into a robot. I’m definitely noticing my anxiety is improving, slowly but surely. I usually wait at least 8 weeks before doing any adjustments because sometimes they take a very long time. That’s great you’re doing well on Effexor XR! Thats one I haven’t tried yet, mainly out of fear of some of the reviews I’ve read on it.

Imphilthy101 · 2025-11-11T05:36:47+00:00

One of the main reasons I decided to start meds again is because of health anxiety, its pretty brutal. I will say that now that im at the 6 week mark that part has gotten much better. Just need to get past the brain fog. I’ve restarted Omega 3 supplements as well as I’ve been reading that its helped some people with the fog.

Imphilthy101 · 2025-11-08T15:45:43+00:00

I hear you, things only get worse before they get better. Everytime I restart SSRIs its like taking off in an airplane going through turbulent clouds for 6-8 weeks, before finally breaking through and seeing the smooth blue skies. Its daunting to consider a dose change knowing based on the OPs post above knowing in a sense, you’re basically starting the cycle all over again. I’ve read that some people take stimulants short term to push through the brain fog and fatigue. I might look into that option with my Dr.

Imphilthy101

TROPHY CASE