Section 720 ILCS 570/402
Possession of Controlled Substances
Except as otherwise authorized by this Act, it is unlawful for any person knowingly to possess a controlled or counterfeit substance or controlled substance analog. A violation of this Act with respect to each of the controlled substances listed herein constitutes a single and separate violation of this Act. For purposes of this Section, “controlled substance analog” or “analog” means a substance, other than a controlled substance, which is not approved by the United States Food and Drug Administration or, if approved, is not dispensed or possessed in accordance with State or federal law, and that has a chemical structure substantially similar to that of a controlled substance in Schedule I or II, or that was specifically designed to produce an effect substantially similar to that of a controlled substance in Schedule I or II. Examples of chemical classes in which controlled substance analogs are found include, but are not limited to, the following: phenethylamines, N-substituted piperidines, morphinans, ecgonines, quinazolinones, substituted indoles, and arylcycloalkylamines. For purposes of this Act, a controlled substance analog shall be treated in the same manner as the controlled substance to which it is substantially similar.