The diabetes mellitus codes are combination codes that include the type of diabetes mellitus, the body system affected, and the complications affecting that body system. As many codes within a particular category as are necessary to describe all of the complications of the disease may be used. They should be sequenced based on the reason for a particular encounter. Assign as many codes from categories E08 – E13 as needed to identify all of the associated conditions that the patient has.

The age of a patient is not the sole determining factor, though most type 1 diabetics develop the condition before reaching puberty. For this reason, type 1 diabetes mellitus is also referred to as juvenile diabetes.

If the documentation in a medical record does not indicate the type of diabetes but does indicate that the patient uses insulin, code E11-, Type 2 diabetes mellitus, should be assigned. Additional code(s) should be assigned from category Z79 to identify the long-term (current) use of insulin, oral hypoglycemic drugs, or injectable non-insulin antidiabetic, as follows:

Proper coding of diabetes during pregnancy distinguishes between pre-existing conditions and those that develop during gestation. This distinction is crucial for accurate patient care and data reporting, ensuring all related conditions are captured.

Codes under categories E08, Diabetes mellitus due to underlying condition, E09, Drug or chemical induced diabetes mellitus, and E13, Other specified diabetes mellitus, identify complications/manifestations associated with secondary diabetes mellitus. Secondary diabetes is always caused by another condition or event (e.g., cystic fibrosis, malignant neoplasm of pancreas, pancreatectomy, adverse effect of drug, or poisoning).

For patients with secondary diabetes mellitus who routinely use insulin, oral hypoglycemic drugs, or injectable non-insulin drugs, additional code(s) from category Z79 should be assigned to identify the long-term (current) use of insulin, oral hypoglycemic drugs, or non-injectable non-insulin drugs as follows: