HCPCS Level II · Procedures and professional services (temporary)
G9959Systemic antimicrobials not prescribed
✓ Active
Source: CMS HCPCS quarterly update, October 2026. Page updated September 29, 2026.
About G9959
G9959 is an HCPCS Level II code in the G series (procedures and professional services (temporary)), describing systemic antimicrobials not prescribed.
It was added to HCPCS effective 01/01/2018.
Its Medicare coverage code is "C", meaning coverage is left to the Medicare contractor's judgment.
Details
- Short description
- Systemic antimicro not presc
- Date added
- 01/01/2018
- Action effective
- 01/01/2018
- BETOS
- Z2
Related G99xx codes
- G9900Screening, diagnostic, film, digital or digital breast tomosynthesis (3d) mammography results were not documented and reviewed, reason not otherwise specified
- G9901Patient age 66 or older in institutional special needs plans (snp) or residing in long-term care with pos code 32, 33, 34, 54, or 56 for more than 90 consecutive days during the measurement period
- G9902Patient screened for tobacco use and identified as a tobacco user
- G9903Patient screened for tobacco use and identified as a tobacco non-user
- G9905Patient not screened for tobacco use
- G9906Patient identified as a tobacco user received tobacco cessation intervention during the measurement period or in the six months prior to the measurement period (counseling and/or pharmacotherapy)
- G9908Patient identified as tobacco user did not receive tobacco cessation intervention during the measurement period or in the six months prior to the measurement period (counseling and/or pharmacotherapy)
- G9910Patients age 66 or older in institutional special needs plans (snp) or residing in long-term care with pos code 32, 33, 34, 54 or 56 for more than 90 consecutive days during the measurement period
- G9911Clinically node negative (t1n0m0 or t2n0m0) invasive breast cancer before or after neoadjuvant systemic therapy
- G9912Hepatitis b virus (hbv) status assessed and results interpreted prior to initiating anti-tnf (tumor necrosis factor) therapy
- G9913Hepatitis b virus (hbv) status not assessed and results interpreted prior to initiating anti-tnf (tumor necrosis factor) therapy, reason not otherwise specified
- G9914Patient initiated an anti-tnf agent
Common questions about G9959
Is HCPCS G9959 still valid?
- Yes. G9959 is active in the CMS October 2026 HCPCS file.
Does Medicare cover G9959?
- Its coverage code is "C": coverage is left to the Medicare contractor's judgment. Check the local coverage determination for your region.