Summary & Overview

HCPCS G2077: Periodic Assessment for Opioid Treatment Program

HCPCS Level II code G2077 represents a periodic assessment service provided by an opioid treatment program practitioner to evaluate medication dosing, treatment response, other substance use disorder treatment needs, patient goals, and related physical, nutritional, and psychiatric needs. The code may be informed by standardized, evidence-based assessments and supports consideration of harm reduction and recovery support services. Nationally, this code is relevant to efforts to standardize comprehensive, ongoing clinical oversight in medication-assisted treatment for opioid use disorder.

Key payers covered in this overview include Aetna, Blue Cross Blue Shield, Cigna Health, UnitedHealthcare, and Medicare. Readers will find a concise summary of the clinical intent of the code, common billing context, payer coverage scope, and typical sites of service. The publication outlines what to expect regarding billing placement — this code is reported in addition to primary service codes — and situates the code within broader clinical management of opioid use disorder. The content also highlights where input was unavailable: associated taxonomies, specific ICD-10 diagnoses, related codes, and service line details are not provided in the input. This summary equips providers, billing staff, and policy analysts with a clear national-level understanding of G2077’s purpose and common operational context.

AetnaBlue Cross Blue ShieldCigna HealthUnitedHealthcareMedicareG2077HCPCS Level IIopioid treatment programperiodic assessmentsubstance use disordermedication-assisted treatmentharm reductionrecovery support

Billing Code Overview

HCPCS Level II code G2077 describes a periodic assessment performed by an opioid treatment program (OTP) practitioner. The service involves periodic review of medication dosing, treatment response, other substance use disorder treatment needs, patient-identified goals, and relevant physical, nutritional, and psychiatric needs. The assessment may be informed by a standardized, evidence-based instrument or by evaluation of need and interest in harm reduction interventions and recovery support services. This code is listed separately in addition to each primary code when billed.

Service type: Periodic assessment for opioid use disorder treatment

Typical site of service: Opioid treatment program (OTP) or other settings where Medicare-enrolled OTP services are provided

Clinical & Coding Specifications

Clinical Context

A 46-year-old patient enrolled in a Medicare-enrolled Opioid Treatment Program (OTP) presents for a periodic assessment with the OTP practitioner (physician, nurse practitioner, or certified addiction counselor). The patient has been stable on buprenorphine-naloxone for opioid use disorder but reports occasional cravings and recent alcohol use. The OTP practitioner conducts a structured review of medication dosing and adherence, assesses treatment response and side effects, screens for other substance use and psychiatric symptoms, reviews nutrition and physical health needs, updates patient-identified recovery goals, and evaluates interest in harm reduction interventions (e.g., naloxone distribution, safer-use counseling) and recovery support services. A standardized, evidence-based assessment tool is administered to quantify symptoms and guide care planning. The periodic assessment is documented in the electronic health record, including medication review, standardized assessment results, recommendations for dose adjustment if clinically indicated, referrals to behavioral health or medical services, and any harm reduction or recovery supports provided or planned. The service is billed separately in addition to primary OTP services for that visit using G2077.

Coding Specifications

Modifier	Description	When to Use
`00`	No modifier (default)	Use when no special circumstances apply to the billed service.
`22`	Increased Procedural Services	Use when the periodic assessment requires substantially greater work or time than usual (e.g., complex medication adjustments, multi-domain evaluation).
`23`	Unusual Anesthesia	Not typically applicable to behavioral health OTP periodic assessments; included only if an unusual anesthesia circumstance were legitimately involved.
`29`	Change of Portfolio (Other Payer)	Use when required by specific payer administrative rules for reporting changes in payer relationships.
`52`	Reduced Services	Use when the periodic assessment was partially performed or truncated (e.g., patient left early).
`53`	Discontinued Procedure	Use when the assessment was started but discontinued due to patient instability or other valid clinical reason.
`78`	Unplanned Return to OR	Not applicable to OTP periodic assessments; listed for completeness when present in modifier set.
`95`	Synchronous Telemedicine Service Rendered via Real-Time Interactive Audio and Video	Use when the periodic assessment is delivered live via interactive telehealth.
`AS`	Physician Assistant, Nurse Practitioner, or Clinical Nurse Specialist Assisting at Surgery	Not applicable to most periodic OTP assessments but included where a specific assistant role is required by payer.
`QK`	Medical Direction of Two, Three, or Four Certified Registered Nurse Anesthetists (CRNAs)	Not applicable to OTP assessments; included for completeness of common CMS modifiers.
`QX`	CRNA Service: With Medical Direction by a Physician	Not applicable to OTP assessments.
`QY`	Medical Direction of One CRNA by an Anesthesiologist	Not applicable to OTP assessments.
`TG`	Prolonged Service with Face-to-Face Contact (Telehealth Modifier)	Use when extended face-to-face time is provided via telemedicine beyond typical visit length and payer requires this modifier.

Taxonomy Code	Specialty	Notes
`2084P0800X`	Addiction Medicine Physician	Physicians who diagnose and manage opioid use disorder and perform periodic OTP assessments.
`363L00000X`	Substance Use Disorder Treatment Provider	Behavioral health clinicians and counselors who contribute to assessment and care planning in OTPs.
`162W00000X`	Nurse Practitioner	NPs who prescribe and manage medications for opioid use disorder in OTP settings.
`163W00000X`	Physician Assistant	PAs who provide follow-up and medication management in OTP programs.
`251B00000X`	Registered Nurse	RNs who perform monitoring, screening, and coordinate harm reduction and recovery support services.

Related Diagnoses

ICD-10 Code	Description	Clinical Relevance
`F11.20`	Opioid dependence, uncomplicated	Primary diagnosis for patients receiving OTP services; indicates ongoing medication management and periodic assessment needs.
`F10.20`	Alcohol dependence, uncomplicated	Common co-occurring disorder evaluated during OTP periodic assessments to guide integrated care and harm reduction.
`F11.21`	Opioid dependence, in remission	Relevant for patients with histories of opioid use disorder undergoing maintenance and monitoring.
`F32.9`	Major depressive disorder, single episode, unspecified	Depression frequently co-occurs and is screened for during periodic assessments to inform referrals and treatment planning.
`F41.1`	Generalized anxiety disorder	Anxiety disorders commonly co-occur and affect treatment response and recovery needs.
`Z91.89`	Other specified personal risk factors, not elsewhere classified	May be used to document behavioral risk factors or barriers to treatment assessed during the visit.
`Z71.51`	Counseling for substance use and substance use disorder	Supportive counseling and care planning often documented alongside the periodic assessment.

Related CPT Codes

CPT Code	Description	Relationship to This Procedure
`99406`	Smoking and tobacco use cessation counseling visit, intermediate, greater than 3 minutes up to 10 minutes	May be provided during the periodic assessment when addressing tobacco use as part of comprehensive substance use care.
`99408`	Alcohol and/or substance (other than tobacco) abuse structured screening and brief intervention, 15 to 30 minutes	Often performed alongside `G2077` when a structured brief intervention is indicated after screening.
`96127`	Brief emotional/behavioral assessment (e.g., depression inventory) with scoring and documentation, per standardized instrument	Used when a quick standardized screening (depression, anxiety, substance use severity) is administered during the periodic assessment.
`99407`	Smoking and tobacco use cessation counseling, intensive, greater than 10 minutes	Used when in-depth cessation counseling is delivered as part of the visit.
`99412`	Prevention counseling and/or risk factor reduction intervention(s) provided to individuals in a group setting	Applicable if group-based recovery support or educational interventions are provided as follow-up to the periodic assessment.