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. Sec. 301 et seq.), to biological products regulated by the food and drug administration under the public health service act (42 U.S.C. Sec. 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. Sec. 301 et seq.).