Patch Test Coding: CPT and ICD-10

What are CPT and ICD-10 codes?
CPT: Coding Procedural Terminology. CPT codes are how offices are paid for procedures they perform. Each code is determined based upon the complexity of the procedure and is also RVU linked.

What is ICD-10-CM?
International Classification of Diseases (10th edition) Clinical Modification. ICD refers to the diagnostic codes. They describe the patient, their diagnosis, and should support the procedures performed.

It is important to remember that insurances pay for procedures (CPT codes) not diagnoses. ICD-10 codes should be used to support CPT codes.


Codes for Evaluation and Management Services

CPT code History1 and
Physical exam2
Medical decision process Time (minutes)3
New Patients (i.e., no professional services within previous 3 years)*
99201 Problem-focused Straight forward 10
99202 Expanded problem-focused Straight forward 20
99203 Detailed Low complexity 30
99204 Comprehensive Moderate complexity 45
99205 Comprehensive High complexity 60
Established Patients
99211 Minimal Minimal 5
99212 Problem-focused Straight forward 10
99213 Expanded problem-focused Low complexity 15
99214 Detailed Moderate complexity 25
99215 Comprehensive High complexity 40

Note: If more than one service or procedure is performed on the same day as an E/M use modifier "25."

* Although dermatologists may receive patients by referral, these are usually coded as new patients not consultations. Consultation codes are used when advice is formally requested by another physician currently providing care for that patient, and influences that patient care. Strict criteria, including extensive documentation, must now be met for billing consultation services.

1 Per Medicare, "history" is often defined based on the chief complaint, history of present illness, a review of systems, and any relevant history (e.g., past, family or social).

2 Per Medicare, 1) a "problem-focused" exam means the affected body area or organ system; 2) an "expanded problem focused" exam means the affected body area or organ system and other related systems; 3) a "detailed" exam means a more extensive exam of the affected body area or organ system and other related organ systems and 4) a "comprehensive" exam means an extensive exam of 12 organ systems or complete exam of a single organ system.

3 Per Medicare, the length of time spent with a patient does not primarily control the level of service billed, unless it constitutes more than 50% of the face-to-face time such as when providing counselling or coordinating care.

Dermatologists, physician's assistants, and nurse practitioners should not use 99204, 99205, or 99215, as these codes require extensive documentation for levels of care rarely performed and/or medically necessary.

Patch Tests - Contact Dermatitis Codes for ICD-10


For complete information about coding procedures, physicians are referred to current versions of the American Academy of Dermatology Coding and Documentation Manual and the American Medical Association's CPT and ICD-10-CM guidance manuals.

  • For each patch test(s), use CPT code 95044 (or 95052 for photo patch tests). According to Medicare guidelines, the number of tests (i.e., allergen patches) must be specified. For T.R.U.E. TEST® panels 1.3 and 2.3, and 3.3, the total number of patches is 36. This number (36) is the multiplier used for the 95044 reimbursement fee.
    Note: Medicare and third party payers can have different patch testing policies, including different maximum allowable tests (i.e., 95044) per beneficiary per year. Carefully review any limitations in payer policies that may impact office procedures and patient care.

  • The level of evaluation and management (E/M) service reported should be based on current history, exam and decision-making criteria, and not solely on time spent with the patient. Support E/M service reporting with clear documentation in the medical record(s).

  • Depending on patient care provided, it may be appropriate to bill for a separately identifiable E/M service that occurs on the same day as patch testing. If this is the case, it should be reported using modifier 25, recognized by most payers.

  • The ICD-10-CM codes for diagnoses of allergic contact dermatitis vary. Use appropriate ICD-10-CM codes (including V codes) to identify diagnoses, symptoms, other conditions, problems and complaints.

Disclaimer: The brief information included here about coding and reimbursement is for educational purposes only. It should not replace current Medicare or specific payer policies, state or federal regulations, medico-legal practice guidelines, or consultation with coding experts or attorneys. Users should always consult payers for final guidance and about changes in coding and reimbursement practices. SmartPractice® and SmartPractice Denmark® assume no liability from the use of this manual.

For more details on patch test reimbursement, contact our customer service department at 1-800-878-3837.