Sorry to hear about your IBS - I suffered from it quite severely for a few years before I began by PGCE but thankfully it's been under control now for a couple of years. One of the biggest impacts for me was when the consultant said it was severe IBS as that immediately made me feel like I hadn't just been making a fuss all along! You say that you've got meds prescribed by a consultant so you've probably had all the advice, but mine put me on a diet free from wholewheat (goes against all healthy eating advice!) and caffeine, prescribed meds and also referred me for specialised hypnotherapy, which I was quite sceptical about but has worked very well. From my own experience I found that I was having to work until the early hours frequently on the PGCE and still very rarely get anywhere near 8 hours sleep a night (a few years into teaching) but fortunately the lack of sleep doesn't affect my IBS in the same way. However, nerves and stress definitely do and I don't think those are really things that can be avoided on the PGCE! I have always been honest on applications etc about IBS (had to go to Occupational Health appt at the beginning of my first job) as I've felt that potentially it could affect my performance in the role, so wanted course / employers to be aware of that from the outset. One of the previous posters makes a good point though about the practicalities of not being able to just leave a class if you do have a sudden bout, as it was definitely something that I have been concerned about on occasions. Fortunately I have only had to do leave the classroom on one occasion to rush off and that was when I had a TA in class, however I don't have any TA time this year so don't know what I'd do if it happened now! As you describe your condition at present I think that you do need think very carefully about whether teaching will make things worse for you, and personally, would definitely recommend being honest about it. Sorry not to be able to be more positive for you. All the best.