Does R21 require prior authorization?

No, R21 does not require prior authorization (high confidence). Code is covered without prior authorization.

`R21` — Rash and other nonspecific skin eruption

ICD-10-CM

No Prior Auth Required

Code is covered without prior authorization (high confidence)

All documentation must be maintained in the patient's medical record, legible, include complete patient identification, dates of service, and the legible signature of the responsible practitioner, and be made available to the contractor upon request.
The submitted medical record must support the use of the selected ICD-10-CM code(s) and the submitted CPT/HCPCS code must describe the service performed.
For dermabrasion, the medical record must describe the beneficiary's rhinophyma disease process that is being treated.
For abdominal lipectomy/panniculectomy, the record must describe the pannus and underlying skin, document chronic intertrigo or related complications, describe functional impairments, document conservative treatments tried and results, and preoperative photographs of the pannus and skin are recommended.

Services that meet the Medicare reasonable and necessary requirements per Local Coverage Determination (LCD) L35090 are covered when billed as reconstructive or medically necessary procedures.
Dermabrasion for treatment of rhinophyma is covered when the medical record documents the beneficiary's rhinophyma disease process supporting medical necessity.
Abdominal lipectomy/panniculectomy is covered when the pannus causes chronic intertrigo (skin irritation, infection, or chafing) and there is documented functional impairment (e.g., difficulty walking, exercising, or activities of daily living) after conservative treatment.
Removal of breast implants as reconstructive breast surgery is covered when the medical record describes a condition that makes implant removal medically reasonable and necessary.
Reduction mammaplasty is covered when the record documents height and weight, clinical signs/symptoms attributed to macromastia, prior therapies and responses, and contains operative and pathology reports with tissue weight removed from each breast and an age‑appropriate mammogram report.
Mastectomy for gynecomastia is covered when glandular breast tissue confirming true gynecomastia is documented, hormonal causes have been excluded by appropriate labs, gynecomastia persists despite correction of underlying causes and medical therapy, and the condition meets ASPS Grade III or IV criteria for males.

A58774 — Billing and Coding: Cosmetic and Reconstructive Surgery

J05

A57473 — Billing and Coding: Allergy Testing

J05

L36402 — Allergy Testing

J05

L39051 — Cosmetic and Reconstructive Surgery

J05

L35001 — Reduction Mammaplasty

Ask Verity about documentation requirements, denial risks, or coverage in your state.