12.— Where a pharmacist working in a retail pharmacy business is presented with a prescription for a branded interchangeable medicinal product and substitutes, in accordance with Chapter 2, a substitute medicinal product for the branded interchangeable medicinal product, no action or other proceeding lies or shall be instituted against the pharmacist or the prescriber, or any other person who is responsible for the acts or omissions of the pharmacist or prescriber, as the case may be, on the ground of the substitution.