Can I take mtx while on antibiotics: Just a thought I... - NRAS


31,279 members37,900 posts

Can I take mtx while on antibiotics

Carolsos profile image

Just a thought I am due to take mtx tonight, do you think it would be best to leave taking mtx until I am over my bladder infection? Anyone any idea? Thanks

17 Replies

Yes I would . The advice from my nurse was to stop MTX with any infection .

Like so much it is hugely individual. Depends on your overall health, the type of antibiotic, the seriousness of the infection and how well controlled your RA is. Always check with your own medical team.

I was always told not to take MTX whilst on antibiotics.

When I was in hospital, having just being diagnosed with RA and started on methotrexate, I was traced as a contact of another patient with meningitis so was advised to have a course of antibiotics as a precaution. My consultant had to be consulted (?!) as to which one I could be prescribed. Check with a medical professional.

In a word

I have RA and have been on mtx for over 12 years, and on an antibiotic as a prophylactic for 6. The mtx still works.

There's two antibiotics that you shouldn't take when on mtx, I've taken a picture of what it says in my mtx monitoring booklet.

Paula-C profile image
Paula-C in reply to Paula-C

Tried to post the picture and it's not appeared. The two are co-trimoxazole (septrin) and trimethoprim. It goes on to say they can react with mtx and can be dangerous.

I've just been given antibiotics & asked if I should miss my mtx dose & was told to continue as normal

Assuming you are on antibiotics, you can check for yourself here

If this link does not work, just go to and click on Interactions in the box on the left.

BNF is British National Formulary aka the pharmacists' bible. Anything on a red background, do not take it with MTX. An out-of-hours GP once prescribed me something on a red background, (Flucloxacillin) even though I had told him I take MTX and asked if what he was giving me was ok to be taken with it. You can see it may produce a severe interaction with MTX. The pharmacist picked up the error, so alternatively, you can check with your pharmacist, but they often look things up on the bnf site anyway. There are a lot of interactions to remember!

Even if the antibiotic is ok with MTX, take advice from the rheumatologist as to whether you should pause MTX to allow you to fight the infection.

Hope that helps.

Garnacha profile image
Garnacha in reply to Bacharia

Oh no, I'm currently taking flucloxacillin 500mg, been on them since last Wednesday, I asked the resident pharmacist at the drs who prescribed them if I needed to stop methotrexate & he said no, the dispensing chemist didn't say anything either & they're pretty switched on with my meds x

Bacharia profile image
Bacharia in reply to Garnacha

I can only add that I reported being prescribed Flucloxacillin while on MTX and it led to a flurry of emails and phone calls apologising about it and the GP who prescribed it was spoken to about it. However, if pharmacists who know you're taking both have raised no objection, I can only guess that they think that the benefits outweigh the risks to your liver.

Garnacha profile image
Garnacha in reply to Bacharia

Thank you, I remembered later that the local pharmacist when I went to get the antibiotics asked when my next blood test was, I'm thinking that she must have thought it odd but perhaps like you say the benefits outweigh the risk, I'm going there today to pick up my leflunimode & will ask them directly now I know, thank you for replying x

I just had a 5 day course of penicillin for a tooth abscess and I was told no methotrexate for 2 weeks after as Penicillin and MTX is a deadly combo. The advice from my consultant there after was always stop your treatment for antibiotics unless it’s going to be needed long term in which case the docs will decide.

Neonkittie17 profile image
Neonkittie17 in reply to D_aisy

Agree. I don’t take penicillin but have been told that anyhow. Always, always best to check with the GP for each type of abx. x

Like many others I have been told by my rheumatology dept and GP to stop methotrexate whenever I have any infection as they can inhibit recovery. As you are taking antibiotics for a bladder infection I would have been advised to stop for two weeks but you should contact your prescriber. I do know that the antibiotic trimethoprim which is often prescribed for urinary infections is contraindicated when taking methotrexate.

HiMy consultant rheumatologist always advised to stop taking methotrexate whilst on antibiotics. I think it’s to do with a reduction in effectiveness of anti biotic whilst on mxt

You may also like...