Is it possible to decline (with six weeks' notice) a senior house officer job which I originally accepted? If so, how should I limit any damage?

I think there are two levels to think about here. On the first, there is the purely contractual: if you have accepted an offer of a post verbally only, then this probably does not constitute a contract between two parties. Even if it did, senior house officers have to give only one month's notice of termination of contract so you are within your strict legal rights under contract and employment law so to do.

On the other hand, there is the professionalism about such a move. I am afraid the practice of accepting posts and then declining them at a later point, almost at the last minute, is becoming more commonplace. Some trusts and indeed consultants take this badly and view it as unprofessional and untrustworthy. I suppose it all depends on whether you think you might want to have a job in that trust ever again. You might wish to talk it through with your educational supervisor in your current post and get some personal advice.

If your appointment was made some time ago, I expect that there were other suitable candidates below you—I guess the trust would ring them to try to find somebody who still wanted the job. If they had to readvertise that would be a complete headache and you would have a permanent black mark against your name. I spent eight hours last week scoring 150 candidates for a short list for foundation programme posts—and that was only half of the applicants apparently.

As far as practicalities are concerned, I would ring up medical staffing and tell them you are now, after some thought, declining their offer (you do not have to give reasons) and follow this up with a short but polite letter.