H40.00 is a "category code," which means it's non-billable. Billable codes require more specificity. Use the list below to navigate to codes that are more specific:
10
H40.001
Preglaucoma, unspecified, right eye
Billable
10
H40.002
Preglaucoma, unspecified, left eye
Billable
10
H40.003
Preglaucoma, unspecified, bilateral
Billable
10
H40.009
Preglaucoma, unspecified, unspecified eye
Billable