Licensees may advertise that they will perform certain designated routine professional services free or at a discount if such advertising claims are truthful. However, no charge shall be made for any other professional services rendered or commodities provided to a patient during any office visit in which free or discounted services are offered or provided unless, prior to the accrual of any charges, the patient shall have been informed of the cost of such additional services and/or commodities and shall have agreed to pay for them.

For the purposes of this section, no separate charge shall be made for the professional evaluation of diagnostic tests or procedures which are provided free or without cost, or at a discount, whether such professional evaluation is made at the time of the initial office visit or at any later time.