This letter has sample wording for resignation from a position in health care due to physical risk or emotional stress. It's appropriate for doctors, nurses, or anyone else in the medical field.
It is with great regret that I must resign from my position with the hospital, effective immediately.
The risk to my health (both mental and physical) has become untenable, and the situation shows no signs of abating.
I went into this profession to help others, but in the end, it seems that I must save myself. I understand that my resignation puts you in a difficult spot regarding staffing, but I am unable to serve even one more day under these conditions.