ICD-10-CM 2027
ICD-10 code for Letrozole Femara long-term drug therapy
From the official ICD-10-CM alphabetic index entry “Long-term (current) (prophylactic) drug therapy (use of) › letrozole (Femara)”. Page updated September 29, 2026.
About coding Letrozole Femara long-term drug therapy
The ICD-10-CM code for Letrozole Femara long-term drug therapy is Z79.811 (Long term (current) use of aromatase inhibitors).
Within Z79.81 (long term (current) use of agents affecting estrogen receptors and estrogen levels), Z79.811 is specifically for long term (current) use of aromatase inhibitors. Related codes cover selective estrogen receptor modulators (SERMs) (Z79.810) and other agents affecting estrogen receptors and estrogen levels (Z79.818).
It is not a CC or MCC, so as a secondary diagnosis it doesn't change the MS-DRG severity level.
In MS-DRG v44.0, it is part of the grouping logic for DRG 951 (Other Factors Influencing Health Status, relative weight 0.5577), in MDC 23 (Factors Influencing Health Status and Other Contacts with Health Services), as a principal or secondary diagnosis. The DRG a claim lands in depends on the principal diagnosis, procedures and any CC/MCC secondary diagnoses.
Common questions about Letrozole Femara long-term drug therapy ICD-10 codes
What is the ICD-10 code for Letrozole Femara long-term drug therapy?
- Z79.811 — Long term (current) use of aromatase inhibitors.
Is Z79.811 billable?
- Yes. Z79.811 is a billable/specific ICD-10-CM code valid for FY2027 (October 1, 2026 – September 30, 2027).
Can Z79.811 be used as a principal diagnosis?
- No. It is not acceptable as the principal diagnosis for an inpatient stay; it may be reported as a secondary diagnosis.
Is Z79.811 a CC or MCC?
- No. Z79.811 is neither a CC nor an MCC under MS-DRG v44.0.