Dear …
RE: Sick Leave Request
Please accept this letter as my formal request for sick leave from my position at __(Name of Organization)__ for __(length of time)__, commencing __(immediately/date/etc.)__.
My doctor has recently informed me that __(briefly describe what the situation is with your health)__ and, therefore, I will require time away to __(briefly describe why absence is needed)__. Please find attached a letter from my doctor stating __(describe briefly what it states)__ .
I appreciate your understanding in this matter and look forward to receiving your acknowledgement and approval soon. Thank you.
Respectfully yours,