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CPT®
90663

CPT® Code 90663
Deleted

CMS: no longer valid. See coding tips.

Official Description

Influenza virus vaccine, pandemic formulation, H1N1

© Copyright 2026 American Medical Association. All rights reserved.

Common Language Description

The CPT® Code 90663 refers to the influenza virus vaccine specifically formulated for the pandemic strain of H1N1, commonly known as swine flu. H1N1 is classified as a subtype of influenza Type A, which is one of the two primary types of influenza viruses, the other being Type B. Vaccines are designed to target specific subtypes of the influenza virus to ensure effectiveness. The pandemic formulation of the H1N1 vaccine may differ from the interpandemic strains, incorporating unique additives, known as adjuvants, that enhance the immune response by increasing the antigen content. These formulations may also vary in dosage to optimize their efficacy during a pandemic situation. An influenza pandemic occurs when a novel strain of the virus emerges and spreads rapidly among the human population, often resulting in a significant lack of pre-existing immunity. This can lead to widespread severe illness and increased mortality rates. The administration of the pandemic formulation of the H1N1 influenza vaccine can be performed through a separately reportable intramuscular injection or intranasal route. It is essential to use this code in conjunction with the appropriate administration code to accurately identify the vaccine product for billing and documentation purposes.

© Copyright 2026 Coding Ahead. All rights reserved.

1. Indications

The influenza virus vaccine, pandemic formulation, H1N1 (CPT® Code 90663) is indicated for individuals who are at risk of contracting the H1N1 influenza virus during a pandemic. This includes populations with little or no pre-existing immunity to the new strain, which can lead to severe illness and increased mortality. The vaccine is particularly important for high-risk groups, such as young children, the elderly, pregnant women, and individuals with underlying health conditions that may predispose them to complications from influenza.

  • High-Risk Populations Individuals with underlying health conditions, young children, the elderly, and pregnant women.
  • Prevention of Severe Illness To reduce the risk of severe morbidity and mortality associated with the H1N1 influenza virus during a pandemic.

2. Procedure

The administration of the H1N1 influenza vaccine involves specific procedural steps to ensure proper delivery and effectiveness of the vaccine. The following steps outline the procedure:

  • Step 1: Patient Assessment Prior to vaccination, a thorough assessment of the patient’s health status is conducted to identify any contraindications or previous adverse reactions to vaccines. This includes reviewing the patient's medical history and current health conditions.
  • Step 2: Vaccine Preparation The vaccine is prepared according to the manufacturer's guidelines, ensuring that it is stored at the appropriate temperature and is within its expiration date. The vaccine may require shaking or mixing to ensure uniformity before administration.
  • Step 3: Administration The vaccine is administered either via intramuscular injection or intranasal route, depending on the formulation. For intramuscular injections, the deltoid muscle is typically the preferred site for adults and older children, while the anterolateral thigh is often used for infants and young children. For intranasal administration, the vaccine is sprayed into the nostrils as per the manufacturer's instructions.
  • Step 4: Post-Administration Monitoring After the vaccine is administered, the patient is monitored for a short period to observe for any immediate adverse reactions. This is crucial for ensuring patient safety and managing any potential side effects.

3. Post-Procedure

Following the administration of the H1N1 influenza vaccine, patients are advised to remain in the healthcare setting for a brief observation period to monitor for any immediate adverse reactions, such as allergic responses. Patients may experience mild side effects, including soreness at the injection site, low-grade fever, or fatigue, which typically resolve within a few days. It is important to provide patients with information regarding potential side effects and when to seek medical attention. Additionally, patients should be encouraged to maintain good hygiene practices and follow public health guidelines to further reduce the risk of influenza transmission.
Short Descr FLU VACC PANDEMIC H1N1
Medium Descr INFLUENZA VACCINE PANDEMIC FORMULATION H1N1
Long Descr Influenza virus vaccine, pandemic formulation, H1N1
Status Code Deleted Code
Global Days XXX - Global Concept Does Not Apply
PC/TC Indicator (26, TC) 9 - Not Applicable
Multiple Procedures (51) 9 - Concept does not apply.
Bilateral Surgery (50) 9 - Concept does not apply.
Physician Supervisions 09 - Concept does not apply.
Assistant Surgeon (80, 82) 9 - Concept does not apply.
Co-Surgeons (62) 9 - Concept does not apply.
Team Surgery (66) 9 - Concept does not apply.
Diagnostic Imaging Family 99 - Concept Does Not Apply
APC Status Indicator Non-Covered Service, not paid under OPPS
Type of Service (TOS) V - Pneumococcal/Flu Vaccine
Berenson-Eggers TOS (BETOS) none
MUE Not applicable/unspecified.
CCS Clinical Classification 228 - Prophylactic vaccinations and inoculations
Date
Action
Notes
2012-01-01 Deleted Deleted
2011-01-01 Changed FDA Approval Pending status changed.
2011-01-01 Added First appearance in code book
2011-01-01 Deleted CMS: no longer valid. See coding tips.
2010-01-01 Changed Code description changed.
2009-01-01 Changed Changed code.
2008-01-01 Added New code
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