The approach you take in writing a letter to your doctor, at least in part, relates to the purpose for which you are writing the letter. For example, you may be sending a formal request to your doctor for a copy of your medical records or that they be sent to your new doctor. Or you may be writing your doctor to thank him for his honest counsel and dedication in helping you get through a serious medical procedure.
Address you physician formally, as in the example, "Dear Dr. Mary Jones." When sending a letter by mail, it is more appropriate to send your letter to your physicians office address rather than her home address.
State the reason that you are writing at the beginning of your correspondence. For instance, if your doctor was determined to discover the reason for symptoms you were having that another doctor disregarded or didn't take seriously enough, state how grateful you are that he did take it seriously.
Express your confidence in your doctor's abilities and as well as his bed side manner. Use complimentary phrases in your correspondence such as, "Because of your dedication I am once again healthy and happy."
Finish your letter by expressing your intention to continue to remain his patient, or if you are relocating, your hopes that you will be fortunate enough to find a new physician as competent and caring as he.