21 C.F.R. § 801.422
(b) Definitions for the purposes of this section. This section uses the following definitions:
Dispenser. A dispenser is any person, as defined in section 201(e) of the Federal Food, Drug, and Cosmetic Act, engaged in the sale of hearing aids to any member of the consuming public or any employee, agent, salesperson, and/or representative of such a person.
Hearing aid. A hearing aid is any wearable device designed for, offered for the purpose of, or represented as aiding persons with or compensating for, impaired hearing.
Prescription hearing aid. A prescription hearing aid is a hearing aid that is not an over-the-counter (OTC) hearing aid as defined in § 800.30 of this chapter or a hearing aid that does not satisfy the requirements in § 800.30 of this chapter.
Rebuilt hearing aid. A prescription hearing aid is “rebuilt” if the manufacturer has inspected and tested the device, made any necessary modifications to ensure it meets applicable regulatory requirements, including the requirements in this section, and adequately reprocessed the device for the next user.
Sale. Sale includes a lease, rental, or any other purchase or exchange for value.
Used hearing aid. A hearing aid is “used” if a user has worn it for any period of time. However, a hearing aid shall not be “used” merely because a prospective user wore it as part of a bona fide hearing aid evaluation to determine whether to select that particular hearing aid for that prospective user. A hearing aid evaluation is “bona fide” if it was conducted in the presence of the dispenser or a hearing health professional selected by the dispenser to assist the prospective user in making a determination.
(c) Labeling. A prescription hearing aid shall bear all of the following labeling:
(1) Outside package labeling. The outside package of a prescription hearing aid shall bear all of the following:
(i) Warnings and other important information. All of the following shall appear on the outside package:
(A) Warning against use in people younger than 18 without prior medical evaluation.

(B) “Red flag” conditions.

(C) Note about device trial options.

(2) Labeling, inside the package. The manufacturer or distributor of a prescription hearing aid shall include a user instructional brochure inside the package and shall make an electronic version available for download without site or customer registration and without requiring purchase of any product or service. The user instructional brochure shall include all of the following:
(i) The following warnings, which shall appear in the following order and prior to any content except the cover page:
(A) Warning against use in people younger than 18 without prior medical evaluation.

(B) “Red flag” conditions, addressed to dispensers.

(C) Warning to dispensers about very high-output devices.

(ii) The following cautions and notices for users, which shall appear prior to any content, except the cover page and the warnings under paragraph (c)(2)(i) of this section:
(A) Caution about hearing protection.

(B) Caution about excessive sound output.

(C) Caution about components lodging in ear.

(D) Note about user expectations.

(E) Note about reporting adverse events to FDA.

(F) Note about hearing loss in people younger than 18 and fitting devices.

(vi) Specific instructions for all of the following:
(3) Labeling on the device. The labeling on a prescription hearing aid itself shall bear all of the following clearly and permanently, except as provided in paragraph (c)(3)(iii) of this section:
(4) Technical specifications. You must determine the technical specification values for the prescription hearing aid labeling in accordance with the test procedures of ANSI/ASA S3.22-2014 (R2020), except as provided in paragraph (c)(4)(ix) of this section for latency. Technical specifications and their associated values that are useful in selecting, fitting, and checking the performance of the prescription hearing aid shall appear in the user instructional brochure or in separate labeling that accompanies the device, including all of the following:
(5) Software device labeling. Prescription hearing aid software that is not distributed with the hearing aid or amplification platform shall meet all of the following labeling requirements. With respect to the information required under paragraphs (c)(1) through (4) of this section, the information must be provided in the software device labeling, as specified in paragraphs (c)(5)(i) through (v) of this section, rather than the locations (e.g., outside package labeling) specified in paragraphs (c)(1) through (4).
(i) Prior to first use of the software or obtaining payment information for the software, whichever occurs first, the labeling must clearly and prominently present all of the following to the prospective user. For each, the labeling must remain visible until the user dismisses it or proceeds to the next step:
(ii) Prior to first use of the software, the labeling must clearly and prominently present all of the following to the prospective user:
[87 FR 50755, Aug. 17, 2022]