Long-term side effects of Trimethoprim?

Posted , 4 users are following.

This discussion has been locked due to a period of inactivity. Start a new discussion

Hi everyone,

I’m new to the forum but was brought here after researching into the longer lasting effects of Trimethoprim. I have taken it three times in my life; each time causing side effects of increasing severity. These were in the form of sciatica, leg numbness (pins and needles) and aseptic meningitis.

The first time I took it was for a kidney infection approx. 10 years ago. I was constantly sick and had lower back pain, which I put down to the kidney infection rather than the Trimethoprim.

The second time was for a suspected kidney infection/UTI. I became very ill immediately after taking Trimethoprim (sciatica, leg cramp and aseptic meningitis) but didn’t realise it was the medication. I wasn’t able to walk properly for 2 weeks after I finished the meds due to severe cramping with the legs and discomfort around the coccyx. I saw my GP about the symptoms and was told that it was nothing to do with the medication.

The third time was for a UTI. Within an hour of the first tablet, I was experiencing aseptic meningitis but much more severe than before. The next morning, after taking medical advice, I took a second tablet. Within the hour I could feel the numbness and cramp work down both legs. Two hours later, I was unable to walk and in excruciating pain with my sciatic nerve. It took weeks for my legs to regain strength and well over a year on, I’m still experiencing symptoms.

What I seem to be finding through researching Trimethoprim online is the commonality of side-effects experienced and the lack of medical professionals a) acknowledging that Trimethoprim is causing severe, immediate side-effects as described, and b) acknowledging that Trimethoprim is causing long term side-effects. The last reaction was so severe that I feel over a year on, I’m still not back to my normal self and I’m becoming increasingly concerned with the sudden onset of joint pain and stiffness.

Has anybody experienced joint stiffness and/or pain after a reaction to Trimethoprim?

What other long-term effects are people experiencing and for how long after?

0 likes, 5 replies


5 Replies

  • Posted

    H Charleysays

    I came across your post when I was looking for different reactions to Trimethoprim because I'm trying to work out how I got my horrible symptoms. I was given a three day course of Trimethroprim which I took and was fine. About a week later the UTI was back and I decided to take the 4 days I had left of the anribiotic (I hadn't thrown the rest out). The day after I took my last tablet I woke up with pins and needles in all my toes. This eventually spread to under my feet throught the day and then after a few more days to my fingers.

    I was beside myself and called the doctor who just said she will do a referral to a neurologist. She also did some bloods and they all came back normal.

    I took my last tablet 2 weeks ago and I still have tingly burning feet. tingly fingers and a painful left shoulder and arm. I get twitches in my muscles and when I have a warm shower I get a rash under my feet and on my face. Once I've cooled down the rash goes away but the prickly sensation is still there permanently.

    I am so worried that I have booked in to see a private neurologist in January but do wonder whether this was caused by trimethroprim. After reading some posts  there seems to be all sorts of reactions to this antibiotic.

    How are you now and have your symtoms got any better? Do you think this could be the Trimethroprim?

    • Posted

      Hi Brigitte,

      Thanks for your response. It sounds like your GP has taken your concerns with the side-effects seriously. It took a good 2 weeks before the pins and needles / cramping eased for me (this was after the 7 day course of Trimethoprim), but it made it near on impossible to walk during that time. Are you finding that the pins and needles you’re experiencing is slowly easing or are you experiencing it with the same intensity?

      I recently had an appointment with a physio to investigate the sciatica and the sudden stiffness / numbness in my joints. The physio is referring me to my GP with a recommendation that I’m referred to a neurologist. Interestingly, I had my bloods taken after my last reaction to Trimethoprim and was told that everything was ‘normal’. Based on that, they wouldn't investigate the reaction any further. The physio told me that a reaction like that wouldn’t necessarily show in general blood tests, and there are specific blood tests they can do to investigate a reaction. As you’re seeing a neurologist in the new year, they’ll know what specific tests are appropriate.

      I never had sciatica before taking Trimethoprim. I never experienced joint pain or stiffness either and my immune system after taking the last prescription of Trimethoprim had never been so low. I am certain that there is a link between the two, as I’ve gone from a fit and healthy young woman to feeling like I’m in my 80’s.

      Is this the first time you’ve taken Trimethoprim?

  • Posted

    Hi charleysays

    I'm glad your pins and needles have gone and I really hope you start feeling more yourself soon. I think it's probably a good idea to see a neurologist even if it's just for peace of mind.

    The pins and needles are still in my feet but not as bad as they were before. It's mainly in my toes but then my muscles under my feet do ache now and then. My shoulder joints are sometimes sore and I still have the odd burning sensation in my arms and calves. I've also found my skin is a lot more sensitive and I tend to welt on my face as well as some pressure uticaria where my clothing is slightly more snug.

    I was in such a panic about it all this week that the doctor re did my bloods and checked for autoimmune, liver and kidneys. All came back clear again. She also says there is nothing more she can do until I've seen the neurologist. I'm feeling relieved that the bloods were clear but a bit nervous as to what the neurologist may say. I'm still convinced that this is a reaction to Trimethoprim as it started on the night of my last tablet. I'm also very slowly weening of a anti anxiety drug called paroxetine but because this reaction happened overnight I just don't know what to think.

    Yes, this was the first time I've taken Trimethoprim.

    Take care


  • Posted

    Hi Brigitte,

    How are you feeling and how did your neurologist appointment go? I went for my appointment recently and they confirmed that the ongoing side effects I'm experiencing are due to trimethoprim. It was such a relief to be 'heard' by a medical professional and not dismissed or played down, which is my experience with GPs.

    I'm due to go back for further investigation in the next couple of months. Would be interested to hear how you got on and whether you're still experiencing your symptoms.

    Take care,


  • Posted

    Hi there

    I took Septrim for a bad throat infection when I lost my voice. Within a few days I woke up one morning thinking I had broken my arm in the night, and my leg and wrist. I was 27. I am now 63 and remain convinced it was the drug. I have had Polyarthritis in evrry bone and area in and around my joints ever since, even in jaw and groin. Experts now call it RA. Had remission periods and every other remedial drug, diet, holistic, herbal you name it. Since 2000 have been successfully drug controlled with methotrexate and solphadol. I also take other tablets I have researched to prevent bone loss and damage.it has ruined my pleasure in life. I even had it whilst pregnant and following most periods of stress which is part of my triggers. Takes forever to get clear of colds coughs and viruses. I know it was the drug but nobody listened then. Reassured I am not alone. Trust me thisthis is the abbreviated version.


Join this discussion or start a new one?

New discussion

Report as inappropriate

Thanks for your help!

We want the forums to be a useful resource for our users but it is important to remember that the forums are not moderated or reviewed by doctors and so you should not rely on opinions or advice given by other users in respect of any healthcare matters. Always speak to your doctor before acting and in cases of emergency seek appropriate medical assistance immediately. Use of the forums is subject to our Terms of Use and Privacy Policy and steps will be taken to remove posts identified as being in breach of those terms.

newnav-down newnav-up