Z79.899 — Other long term (current) drug therapy
Is Z79.899 billable?
Yes — Z79.899 is billable for FY2027. Z79.899 is a valid, billable ICD-10-CM code at the highest level of specificity in its branch. Z79.899 may be submitted for encounters from October 1, 2026 through September 30, 2027.
Z79.899 at a glance
| Code | Z79.899 |
|---|---|
| Description | Other long term (current) drug therapy |
| Billable | Yes |
| Code set | ICD-10-CM FY2027 |
| Valid for encounters | October 1, 2026 – September 30, 2027 |
Which MS-DRGs does Z79.899 group to?
Z79.899 sits in MDC 23 and helps define the logic of 2 MS-DRGs (version 44, FY2027). Which one a stay actually groups to also depends on procedures and secondary diagnoses.
- 949Aftercare with CC/MCCmedical
- 950Aftercare without CC/MCCmedical
How is Z79.899 listed in the Alphabetic Index?
These are the routes through the Alphabetic Index that lead to Z79.899. They show the wording a clinician may have documented, which often differs from the Tabular description.
- Long-term › drug, specified NEC (current) (prophylactic) drug therapy (use of)
- Prophylactic › medication
- Prophylactic › administration of › drug
- Therapy › drug, long-term › drug, specified NEC
Excludes2 — not included here — inherited from Z79
The conditions below are not part of Z79.899, but a patient may have both at the same time. When documentation supports it, Z79.899 and the excluded code may both be reported.
Code also — inherited from Z77-Z99
Two codes may be needed to describe the condition fully. Whether Z79.899 is sequenced first depends on the reason for the encounter.
- any follow-up examination (Z08-Z09)
Code also — inherited from Z79
Two codes may be needed to describe the condition fully. Whether Z79.899 is sequenced first depends on the reason for the encounter.
- any therapeutic drug level monitoring (Z51.81)
How long has Z79.899 existed?
Z79.899 has been in ICD-10-CM since at least FY2016, the earliest fiscal year on record here.
Derived from the official order files for FY2016–FY2026. FY2017 and FY2020 publish no order file, so those years are not covered.