Methotrexate and brain fog

Husband saw neurologist yesterday due to his increasing memory loss and cognitive dysfunction. It's progressing and he was concerned as his father had early on set Alzheimer's. The specialist agreed he is having problems but has linked it to Methotrexate. Anyone else having similar issues? By the way his RA specialist had only this week told him Methotrexate doesn't cause this problem. The neurologist on the hand, say methotrexate can cause dementia to progress. Research has also found this: Methotrexate may cause the following symptoms that are related to brain fog (forgetfulness; confusion; slowed thinking; distractability; depersonalization; inability to remember words when speaking or writing):




Progressive multifocal leukoencephalopathy. This symptom may occur with long-term high dose use

Pseudobulbar palsy

Reduced thinking ability

Reduced thinking ability/mental clarity

Stroke caused by blockage of the arteries that supply blood to the brain

17 Replies


You can get a good idea of this medication on DRUG.COM.( small case).

I understand from this extensive list that this drug can cause problems as shown above. A great deal of this script is complex, although you can pick up the general way that they explain this medication

Remember I am not a GP and because of the complexities of this medications contraindications I would strongly advise that you look at this above site. When informed go back to your RA nurse or RA Specialist and explain your concerns after taking a copy of the pages mentioned above.

Also I can confirm that I am unable to take DMARD medications as I also suffer from severe contraindications.

You also need to understand that possibly, you may be refused Biologic treatments without the medications mentioned in the DMARD list of medications. Although this may not be the case in your NHS area. There is a good list of DMARD medications that suffer different contraindications to Methotrexate so all will not be lost if Biologics are given with other medications, in that group.

Good luck



Taken from Drugs. com. My understanding.

1 like

Thank you - my husband has a number of side effects with various DMARDS- trouble is the dermatologist now thinks his rash, itching and high CRP levels are caused by Methotrexate but he needs the Methotrexate to stop the rash and itching - its having no effect on his RA. The brain fog is something to add to the mix along with other side affects - he did discuss biologicals when he saw rhumy specialist this week but as his RA not active he is not eligible - however given the side effects with biologicals - same story. My husband did say if he'd known what he knows now when first offered DMARDS 4 years ago he would not have taken them. He is no better off, still taking Naproxen and co-codemol to reduce the pain - the DMARDs were 'sold' to him that he would be able to come off all pain killers - rubbish as we now know.

1 like

I think most of us who are taking or have taken MTX can relate to some degree of cognitive issues but when there's family history of Alzheimer's it must be even more concerning & one is probably bound to question if it's the cause of problems if a Specialist suggests it is. What we call brain fog seems to be pretty much the norm but as I understand it the higher the dose the greater the possibility of experiencing increased side effects so if it was being used in the higher doses used for chemotherapy it could be a higher risk. That said we all react differently to meds but what concerns me is that the two Specialists disagree. Your h needs clarification, this isn't something that can be dismissed by his Rheumy is it, if it is the cause?

I do hope it's not due to MTX but neither do I hope it's early days dementia, it must be so disconcerting that it's thought the Neuro guy is of the opinion a med prescribed to help him could be causing such problems. What is his line of thinking do you know, what testing is he arranging to confirm his conclusion?

My thoughts are with you both. x


It is worrying - the neurologist has arranged a brain scan - so we'll see what the outcome is from that. Apparently he is seeing more and more RA patients that are taking DMARDS - not just Methotrexate - with cognitive issues - very much a concern. Husbands Rhumy specialist also said rash and high CRP nothing to do with RA - then a few months later announced he is running joint clinic with dermatologist as seeing a number of RA patients with rashes (not necessarily Psoriatic) - think the guy needs some training or is it RA specialists are making it up as they go and as more and more issues are arising with DMARDs they are having to address them - either way sometimes feel RA patients are guinea pigs!

1 like

It's concerning, particularly as his Rheumy appears to be contradicting himself. Whether it's relative or not it's not the answer your h is looking for is it? I do hope that this is not a permanent thing or the beginning of dementia, but it did cause me to look into if any research had been done & to be honest I was quite surprised. There have been quite a few studies performed but it was one particular study conducted in the US I found interesting. Whilst not every one has had every DMARD many have had MTX so as long as you understand I'm not challenging your h's Neurologists findings I'm certainly in no position to so that's not my reason for mentioning this. No, what got my attention was that it states that cognitive issues aren't considered unusual (which we know as many can relate to brain fog) but it suggests rather than the meds used to treat it's the disease itself which causes cognitive problems, the only exception being glucocorticoids which the majority of us will have taken or be taking so the one drug we probably all have in common. It does state that CV issues can also play a part, which of course we know is of real concern as inflammation can affect the heart which itself can cause cognitive impairment. The notes on the study are quite long winded but if you'd like me to send the link I will no probs.


Hello Liluc

Ten years or so I was given a brain scan after I was finished with DMARD. In my case there were changes that seemed to have caused problems then, and still do today. My Father and a close aunt both suffered from Dementia and believe me when I say it makes me worry thinking about it now. With my condition they put it down to blocked, small veins caused by plaques. I do not know if this was caused by PA.

and was not told that problems could be caused by DMARD medications and mental health

All I can suggest is research at the well head and confirm your worries so you can be given some form reassurance that all is ok. It is difficult for lay people to take into consideration contraindications. It is generally your medical team that should be taking all into consideration.

The main problem with RA that I can see is specialists with hands on their hearts try and find relief and some form of control of conditions such as various forms of RA and this can push Dmard medications onto a patient suffering chronic pain. We all need to understand that it is us the patient that needs to make informed decisions on the medications that they push down their throats. We also need to understand that many specialists should let patients make informed choices when risks are known about,When strong medications are used for other types of illness such as cancer.



I agree that we should make informed choices about what meds we take as it is our bodies, but I think that the the specialist should respect that when a patient makes a decision not to take a med because of the possible side effects or because the correct procedure hasnt been followed the patient should be given alternatives not dismissed and discharged as happened to me recently. Joolz.x


Hello Joolz

Yes that happened to me when I moved to a different area.

Now I suppose if I need a referral, sad to say will need too travel over thirty miles to get one.

Sometimes an attitude a Specialist has can be a lot to be desired as it can affect over associated treatments that you may need



If you believe that it is the methotrexate causing the Dementia like symptoms, you can consult with the doctor and tell your doctor you want to stop taking it and see if the symptoms go away, really its the only way to tell quickly. The RA isn't going anywhere, and if it is the MTX you should know soon enough, if his symptoms improve when not taking it.

Everyone reacts different to any of the DMARDS and the Biologics. Some work excellent for some, yet not for others, and it can take years to find the correct meds and dosage to manage your disease, we all are so individual in our care needs.

I think MTX is an excellent medication and it really gives so many people the relief they need, however its not for everyone. MTX helped me in regards to my inflammation, it was a miracle relief from years and years of suffering..... but the side effects were not tolerable. Along with losing 50% of my hair, developing beaus lines in my nails, chronic infection, as well as some of the symptoms you describe.

I lost my ability to navigate and critically think. EX. When I had to go to the bank, I could picture the bank in my mind...but I could not drive there because i could not remember how to navigate there, I literally lost all sense of direction...and this was my bank for over 20 years.

At work I had to write a health and safety test, I would read a sentence and answer a question. I had to keep reading over and over....I could not retain any memory of what I read....and my Supervisor was quite annoyed the "I" the go-to safety girl! couldn't do the test. These are only a few examples. This dementia like issues crept up on me and I did not notice...however others did, I got lost going to my weekly group meeting, I just kept driving around trying to remember where the library was (I lived here for over 40 years) yet I forgot how to get there. When I arrived late I told them I got stuck in traffic, too embarrassed to say I got lost.

Other people actually started joking that I had Dementia.

Once I was off MTX my brain cleared and I am fine now, thinking clearly at 46 years old.

I hope you get some answers.


I just read this article last week linking chemo drugs to brain fog. Since MTX is a chemo drug, even thiugh we use it in much smaller doses, I think it stands to reason that we might get some of the same symptoms.

google: UBC chemo drug brain fog

My stupid iPad isn't working right so I can't send the proper link.

When first diagnosed, I found a site where a rheumatologist recommended taking MTX on Fridays or Saturdays due to its impact on cognitive function (people complained of braing fog, not thinking clearly and forgetting things). His theory was that way you could have proper brain function by Monday when back at work.

I'd personally rather my brain just worked all the time, but the MTX is working so I guess I'm stuck with forgetfulness and short term memory impairment for now...


Thank you I will check it out. Interestingly my husband was told to take methotrexate on a Friday so he'd be ok for work on a Monday. So for last 4 years he's felt crap all weekend, especially on a Sunday and it takes him till Tuesday to start feeling something like. I'm glad the methotrexate is helping you, and whilst it is there is no other option x take care.


Thank you...I have been taking this for 10 + years.  Lately I think I'm just losing it.


Hi, I came across your post as I was looking for information regarding Methotrexate and dementia. About 7 years ago my dad started weekly injections of Methotrexate for RA and soon after started experiencing trouble with words. A year or so later he was diagnosed with FTD but it has progressed very slowly and only in the last few months has his dementia moved beyond language problems. It just doesn't seem to fit any of the types of FTD so I was looking for some other connection. Did your husband find any connection between methotrexate and his cognitive issues?


Hi, he started on Methotrexate in 2011 and his speech issues, plus finding his way round (he sometimes doesn't recognise where he is going even though he may have traveled that route many times before). He has complained of his difficulties in recognising words when speaking, for the last three years but it was only last year that the specialist referred him on, he did this I turned up at an appointment with some info showing FTD is a side effect of Methotrexate., rare but it is recorded. He had an Addenbrookes test but due to a mass exodus of dementia specialists at our hospital no one bothered to contact him. Again it was raised early this year and he got a letter from the RA specialist telling him to stop the methotrexate immediately pending another Addenbrooke test. He had the test and there was a slight deterioration which the RA specialist said was minor and that he is ok to resume methotrexate as the Cognitive Impairment (they won't label it as dementia) was slow to progress - see the Alzeimers website they do a very good fact sheet. Given other issues and my husbands concerns re what he feels is a worsening cognitive impairment, he has refused to go back on any methotrexate. The methotrexate never stopped the pain so he is now managing the RA with Naproxen and cocodemol. I really do hope your dad gets sorted and the cognitive issues progress very slowly. It's a worry.


Hi, Thanks so much for your response! My dad moved interstate this week and the first thing the doctor (GP) not specialist, did was take him off methotrexate so I will see if there is any improvement. He is in a home now - that's how bad his dementia has become! I also want him tested for Lyme as RA and cognitive issues can be misdiagnoses for that - and they are now saying it is far more widespread than previously thought - I'm trying to rule out everything. Hope your husband's cognitive issues improve now he is off the MTX. Thanks again. Your posts have really helped!


Hi. Out of curiosity, what has been the outcome of your dad coming off the methotrexate. My mum has been on a high dose of oral methotrexate and has had progressively worse issues with memory loss since started the meds.Doctors now think she may have early onset alzheimers. She had no symptoms what so ever before starting the meds.


His memory has got worse. The neurologist says there is link between methotrexate and cognitive dysfunction but the RA specialist says not, however the RA specialist says methotrexate has no side effects! John came off it of his own accord last April, but each time he stops taking it within a few months he starts with itching and sore skin. He's tried goodness knows how many creams and antihistamine but in the end has very reluctantly gone back on a low dose of oral methotrexate as this is the only drug to ease the symptoms. They've now eased so he's coming off it again at the end of January. His RA is fine, it's the other side effects, that he never had pre methotrexate that's causing him the issues. If only we could turn back time, he'd have never taken methotrexate. Bit like using a sledgehammer to crack a nut. How many more people have they put on this drug when not needed? Hope your mum is ok x


You may also like...