Nothing in this chapter applies to prescription drugs and devices regulated by the food and drug administration under the federal food, drug, and cosmetic act (21 U.S.C. § 301 et seq.), to biological products regulated by the food and drug administration under the public health service act (42 U.S.C. § 262 et seq.), or to any substance that may be lawfully sold over-the-counter without a prescription under the federal food, drug, and cosmetic act (21 U.S.C. § 301 et seq.).