No pharmacy may fail to provide to any consumer the discounts and services stated on the poster, under the eligibility, price, and other terms there stated. Every sale of one of the 100 most commonly used prescription drugs, in a quantity and strength which requires the price of the drug to be posted, shall be at the posted price, unless a decrease in price is authorized by subchapter III of this chapter.
D.C. Code § 48-801.05