ICD10BillableValid for clinical use
ICD-10 Code Z79.899: Other long term (current) drug therapy
Z79.899 is a billable ICD-10 diagnosis code used to classify Other long term (current) drug therapy in medical records and claims. You may see this code in hospital records, discharge summaries, insurance claims, encounter documentation, referrals, or other healthcare billing and coding records. ICD-10 codes are diagnosis classification codes used in healthcare records, reporting, coding workflows, and billing support. This code sits within the broader ICD-10 area for Factors influencing health status and contact with health services (Z00-Z99).
Reviewed by HealthAssure Clinical TeamUpdated 26 May 2026
What is this code?
ICD-10 codes are diagnosis classification codes used in healthcare records, reporting, coding workflows, and billing support. This code sits within the broader ICD-10 area for Factors influencing health status and contact with health services (Z00-Z99).
When is it used?
- May be used when a clinician documents other long term (current) drug therapy in a patient's medical record.
- May appear in hospital records, claims, referrals, and clinical documentation.
- This code can be used as a clinically usable diagnosis entry in standardized coding workflows.
What it does not mean
- A code alone does not explain severity, treatment plan, or outcome.
- A medical code should not be treated as a substitute for a doctor's diagnosis or advice.
Code hierarchy
chapter
21Factors influencing health status and contact with health services (Z00-Z99)
block
Z77-Z99Persons with potential health hazards related to family and personal history and certain conditions influencing health status
category
Z79Long term (current) drug therapy
category
Z79.8Other long term (current) drug therapy
category
Z79.89Other long term (current) drug therapy
currentZ79.89
Where you may see this code
You may see this code in hospital records, discharge summaries, insurance claims, encounter documentation, referrals, or other healthcare billing and coding records.
Related specialists
General Physician
Related codes
Sibling codes
Coverage-related procedures and services
HCPCS G0480high
DRUG TEST(S), DEFINITIVE, UTILIZING (1) DRUG IDENTIFICATION METHODS ABLE TO IDENTIFY INDIVIDUAL DRUGS AND DISTINGUISH BETWEEN STRUCTURAL ISOMERS (BUT NOT NECESSARILY STEREOISOMERS), INCLUDING, BUT NOT LIMITED TO GC/MS (ANY TYPE, SINGLE OR TANDEM) AND LC/MS (ANY TYPE, SINGLE OR TANDEM AND EXCLUDING IMMUNOASSAYS (E.G., IA, EIA, ELISA, EMIT, FPIA) AND ENZYMATIC METHODS (E.G., ALCOHOL DEHYDROGENASE)), (2) STABLE ISOTOPE OR OTHER UNIVERSALLY RECOGNIZED INTERNAL STANDARDS IN ALL SAMPLES (E.G., TO CONTROL FOR MATRIX EFFECTS, INTERFERENCES AND VARIATIONS IN SIGNAL STRENGTH), AND (3) METHOD OR DRUG-SPECIFIC CALIBRATION AND MATRIX-MATCHED QUALITY CONTROL MATERIAL (E.G., TO CONTROL FOR INSTRUMENT VARIATIONS AND MASS SPECTRAL DRIFT); QUALITATIVE OR QUANTITATIVE, ALL SOURCES, INCLUDES SPECIMEN VALIDITY TESTING, PER DAY; 1-7 DRUG CLASS(ES), INCLUDING METABOLITE(S) IF PERFORMED
Source: CMS coverage guidance
HCPCS G0482high
DRUG TEST(S), DEFINITIVE, UTILIZING (1) DRUG IDENTIFICATION METHODS ABLE TO IDENTIFY INDIVIDUAL DRUGS AND DISTINGUISH BETWEEN STRUCTURAL ISOMERS (BUT NOT NECESSARILY STEREOISOMERS), INCLUDING, BUT NOT LIMITED TO GC/MS (ANY TYPE, SINGLE OR TANDEM) AND LC/MS (ANY TYPE, SINGLE OR TANDEM AND EXCLUDING IMMUNOASSAYS (E.G., IA, EIA, ELISA, EMIT, FPIA) AND ENZYMATIC METHODS (E.G., ALCOHOL DEHYDROGENASE)), (2) STABLE ISOTOPE OR OTHER UNIVERSALLY RECOGNIZED INTERNAL STANDARDS IN ALL SAMPLES (E.G., TO CONTROL FOR MATRIX EFFECTS, INTERFERENCES AND VARIATIONS IN SIGNAL STRENGTH), AND (3) METHOD OR DRUG-SPECIFIC CALIBRATION AND MATRIX-MATCHED QUALITY CONTROL MATERIAL (E.G., TO CONTROL FOR INSTRUMENT VARIATIONS AND MASS SPECTRAL DRIFT); QUALITATIVE OR QUANTITATIVE, ALL SOURCES, INCLUDES SPECIMEN VALIDITY TESTING, PER DAY; 15-21 DRUG CLASS(ES), INCLUDING METABOLITE(S) IF PERFORMED
Source: CMS coverage guidance
HCPCS G0483high
DRUG TEST(S), DEFINITIVE, UTILIZING (1) DRUG IDENTIFICATION METHODS ABLE TO IDENTIFY INDIVIDUAL DRUGS AND DISTINGUISH BETWEEN STRUCTURAL ISOMERS (BUT NOT NECESSARILY STEREOISOMERS), INCLUDING, BUT NOT LIMITED TO GC/MS (ANY TYPE, SINGLE OR TANDEM) AND LC/MS (ANY TYPE, SINGLE OR TANDEM AND EXCLUDING IMMUNOASSAYS (E.G., IA, EIA, ELISA, EMIT, FPIA) AND ENZYMATIC METHODS (E.G., ALCOHOL DEHYDROGENASE)), (2) STABLE ISOTOPE OR OTHER UNIVERSALLY RECOGNIZED INTERNAL STANDARDS IN ALL SAMPLES (E.G., TO CONTROL FOR MATRIX EFFECTS, INTERFERENCES AND VARIATIONS IN SIGNAL STRENGTH), AND (3) METHOD OR DRUG-SPECIFIC CALIBRATION AND MATRIX-MATCHED QUALITY CONTROL MATERIAL (E.G., TO CONTROL FOR INSTRUMENT VARIATIONS AND MASS SPECTRAL DRIFT); QUALITATIVE OR QUANTITATIVE, ALL SOURCES, INCLUDES SPECIMEN VALIDITY TESTING, PER DAY; 22 OR MORE DRUG CLASS(ES), INCLUDING METABOLITE(S) IF PERFORMED
Source: CMS coverage guidance
HCPCS G0481high
DRUG TEST(S), DEFINITIVE, UTILIZING (1) DRUG IDENTIFICATION METHODS ABLE TO IDENTIFY INDIVIDUAL DRUGS AND DISTINGUISH BETWEEN STRUCTURAL ISOMERS (BUT NOT NECESSARILY STEREOISOMERS), INCLUDING, BUT NOT LIMITED TO GC/MS (ANY TYPE, SINGLE OR TANDEM) AND LC/MS (ANY TYPE, SINGLE OR TANDEM AND EXCLUDING IMMUNOASSAYS (E.G., IA, EIA, ELISA, EMIT, FPIA) AND ENZYMATIC METHODS (E.G., ALCOHOL DEHYDROGENASE)), (2) STABLE ISOTOPE OR OTHER UNIVERSALLY RECOGNIZED INTERNAL STANDARDS IN ALL SAMPLES (E.G., TO CONTROL FOR MATRIX EFFECTS, INTERFERENCES AND VARIATIONS IN SIGNAL STRENGTH), AND (3) METHOD OR DRUG-SPECIFIC CALIBRATION AND MATRIX-MATCHED QUALITY CONTROL MATERIAL (E.G., TO CONTROL FOR INSTRUMENT VARIATIONS AND MASS SPECTRAL DRIFT); QUALITATIVE OR QUANTITATIVE, ALL SOURCES, INCLUDES SPECIMEN VALIDITY TESTING, PER DAY; 8-14 DRUG CLASS(ES), INCLUDING METABOLITE(S) IF PERFORMED
Source: CMS coverage guidance
HCPCS G0659high
DRUG TEST(S), DEFINITIVE, UTILIZING DRUG IDENTIFICATION METHODS ABLE TO IDENTIFY INDIVIDUAL DRUGS AND DISTINGUISH BETWEEN STRUCTURAL ISOMERS (BUT NOT NECESSARILY STEREOISOMERS), INCLUDING BUT NOT LIMITED TO GC/MS (ANY TYPE, SINGLE OR TANDEM) AND LC/MS (ANY TYPE, SINGLE OR TANDEM), EXCLUDING IMMUNOASSAYS (E.G., IA, EIA, ELISA, EMIT, FPIA) AND ENZYMATIC METHODS (E.G., ALCOHOL DEHYDROGENASE), PERFORMED WITHOUT METHOD OR DRUG-SPECIFIC CALIBRATION, WITHOUT MATRIX-MATCHED QUALITY CONTROL MATERIAL, OR WITHOUT USE OF STABLE ISOTOPE OR OTHER UNIVERSALLY RECOGNIZED INTERNAL STANDARD(S) FOR EACH DRUG, DRUG METABOLITE OR DRUG CLASS PER SPECIMEN; QUALITATIVE OR QUANTITATIVE, ALL SOURCES, INCLUDES SPECIMEN VALIDITY TESTING, PER DAY, ANY NUMBER OF DRUG CLASSES
Source: CMS coverage guidance
CPT 80307high
DRUG TEST(S), PRESUMPTIVE, ANY NUMBER OF DRUG CLASSES, ANY NUMBER OF DEVICES OR PROCEDURES; BY INSTRUMENT CHEMISTRY ANALYZERS (EG, UTILIZING IMMUNOASSAY [EG, EIA, ELISA, EMIT, FPIA, IA, KIMS, RIA]), CHROMATOGRAPHY (EG, GC, HPLC), AND MASS SPECTROMETRY EITHER WITH OR WITHOUT CHROMATOGRAPHY, (EG, DART, DESI, GC-MS, GC-MS/MS, LC-MS, LC-MS/MS, LDTD, MALDI, TOF) INCLUDES SAMPLE VALIDATION WHEN PERFORMED, PER DATE OF SERVICE
Source: CMS coverage guidance
Coding guidelines
Common synonyms
Other long term (current) drug therapyOther long termOther long term current drug therapy
Frequently asked questions
About this content
This page is prepared by HealthAssure's clinical team using official coding standards from ICD-10. AI tools assist with drafting explanations, which are then reviewed and verified by healthcare professionals for accuracy. This content is for informational purposes and does not replace professional medical advice. Meet our team.