Wiki diagnosis code for annual blood work

[vragsdale]

This is a general diagnosis coding question. If patient presents for annual visit and has no complaints but does have personal history of Hypertension, what would you use for diagnosis code on lab. Patient is maintained on hypertensive medication. They present with no complaints.
Your thoughts and thanks.

 

[irishhawk]

perhaps Z00 that's Z zero zero, not "zoo" 4th/5th digit required.