Summary & Overview

HCPCS S0023: Injection of Cimetidine Hydrochloride, 300 mg

HCPCS Level II code S0023 denotes an injection of cimetidine hydrochloride, 300 mg, used for histamine H2 receptor antagonism. The code is relevant for billing drug administration of this specific injectable formulation across outpatient and ambulatory settings. National payers recognize HCPCS Level II codes for reporting and reimbursement of drugs and supplies furnished to patients where HCPCS coding is required.

Key payers addressed in this analysis include Aetna, Blue Cross Blue Shield, Cigna Health, UnitedHealthcare, and Medicare. Readers will find a concise overview of what S0023 represents clinically, the typical sites of service for administration, and which major payers commonly process claims for this injectable medication. The publication outlines available benchmarks and coverage considerations, notes common modifiers associated with injectable drug services, and summarizes policy implications relevant to payers and billing professionals. Where payer-specific policies or fee benchmarks are not provided in the input, the report notes that data is not available in the input.

This summary is intended for billing managers, revenue cycle staff, and policy analysts seeking a quick national overview of HCPCS Level II code S0023 and what to expect when coding for injection of cimetidine hydrochloride, 300 mg.

AetnaBlue Cross Blue ShieldCigna HealthUnitedHealthcareMedicareS0023HCPCS Level IIinjectioncimetidinedrug-administrationoutpatientmedication-codingbilling

Billing Code Overview

HCPCS Level II code S0023 represents an injection of cimetidine hydrochloride, 300 mg. This entry is a drug administration service for the medication cimetidine hydrochloride supplied in a 300 mg dose.

Service type: Injection medication administration
Typical site of service: Ambulatory clinic or other outpatient setting where injectable medications are administered

Clinical & Coding Specifications

Clinical Context

A typical patient is an adult presenting to an outpatient infusion center, emergency department, or physician office with gastroesophageal reflux disease (GERD), peptic ulcer disease, or acute upper gastrointestinal bleeding requiring parenteral H2-receptor antagonist therapy. The clinician orders S0023 (injection, cimetidine hydrochloride, 300 mg) when oral administration is not feasible, when rapid acid suppression is required, or when intravenous therapy is indicated for inpatient bridging. Workflow: clinician documents diagnosis and indication in the medical record; pharmacy prepares S0023 per institutional protocol; nursing verifies patient identity, allergies, and IV access, and administers the injection intramuscularly or intravenously as ordered; post-injection monitoring for adverse effects (e.g., hypotension, bradycardia, local irritation) is performed; coder assigns S0023 with appropriate ICD-10 diagnosis and adds clinically appropriate modifier(s) to reflect circumstances of service, if required by payer rules.

Coding Specifications

Modifier	Description	When to Use
`00`	Default/No modifier	Use when no special circumstances apply.
`22`	Increased procedural services	Use when administration required substantially greater resources or time due to complexity.
`23`	Unusual anesthesia	Use if administration required while the patient is under general anesthesia unrelated to the injection itself.
`52`	Reduced services	Use when the injection service is partially reduced or not completed as planned.
`53`	Discontinued procedure	Use when administration was started but halted for patient safety or clinical reasons.
`54`	Surgical care only	Rare for injectable medication; use if another provider billed global care and this provider provided only intraoperative care.
`55`	Postoperative care only	Use if provider only furnished postoperative medication-related care.
`62`	Two surgeons	Use when two physicians of different specialties jointly perform portions of a complex procedure requiring the medication and both report.
`AS`	Ambulatory surgical center facility	Use to indicate the service was provided in an ASC when applicable for facility billing.
`QX`	Competent registered nurse practitioner	Use when a qualified non-physician practitioner performed the service within scope and payer accepts modifier.

Taxonomy Code	Specialty	Notes
`207RG0400X`	Gastroenterology	Gastroenterologists may order/administer parenteral acid suppression for GI bleeding or severe GERD.
`207L00000X`	General Surgery	Surgeons may use intravenous H2-blockers perioperatively for upper GI procedures.
`207T00000X`	Emergency Medicine	Emergency physicians commonly administer parenteral cimetidine for acute GI bleeding or allergic reactions when indicated.
`163W00000X`	Pharmacy	Pharmacists prepare and verify `S0023` for administration and dosing.
`363A00000X`	Family Medicine	Primary care or urgent care physicians may administer or order `S0023` when IV therapy is needed acutely.

Related Diagnoses

ICD-10 Code	Description	Clinical Relevance
`K21.9`	Gastroesophageal reflux disease without esophagitis	GERD may require parenteral H2 blockade when oral therapy is not possible.
`K25.9`	Acute gastric ulcer, unspecified as acute or chronic, without hemorrhage or perforation	Peptic ulcer disease is an indication for acid suppression; parenteral cimetidine may be used when oral route is contraindicated.
`K26.9`	Duodenal ulcer, unspecified, without hemorrhage or perforation	Duodenal ulcer management can include IV H2-blockers in acute care.
`K92.2`	Gastrointestinal hemorrhage, unspecified	In acute upper GI bleeding, parenteral H2-antagonists can be used as part of medical management.
`R11.0`	Nausea with vomiting	When oral anti-secretory therapy cannot be tolerated because of vomiting, IV administration may be indicated.
`T88.1`	Other complications following infusion, transfusion and therapeutic injection	Included as a potential complication code if adverse reaction to `S0023` occurs during administration.
`Z79.899`	Other long term (current) drug therapy	Use when patient is on ongoing acid suppression therapy and requires inpatient parenteral dosing.

Related CPT Codes

CPT Code	Description	Relationship to This Procedure
`96372`	Therapeutic, prophylactic, or diagnostic injection (specify substance or drug); subcutaneous or intramuscular	Often used when `S0023` is administered intramuscularly in an office setting; documents the injection administration service by the clinician.
`96365`	Intravenous infusion, for therapy, prophylaxis, or diagnosis; initial, up to 1 hour	Used when `S0023` is administered as part of an IV infusion session or continuous infusion requiring separate infusion service reporting.
`36415`	Collection of venous blood by venipuncture	Frequently performed before or during care to assess hemoglobin, hematocrit, or labs relevant to GI bleeding prior to or after `S0023` administration.
`92950`	Cardiopulmonary resuscitation (CPR), emergency	Included here because if adverse reaction occurs during administration requiring resuscitative efforts, this code may be reported for emergency care delivered.
`99070`	Supplies and materials (e.g., bandages, vacutainers) used directly by provider	Used to report non-routine supplies related to preparation or administration of injectable medication when payer allows.