(a) It is unlawful for any person to possess a counterfeit substance unless the counterfeit substance was obtained:
(1) Directly from or pursuant to a valid prescription or an order of a practitioner while acting in the course of his or her professional practice; or
(2) As otherwise authorized by this chapter.
(b) Any person who violates this section with respect to:
(1) A Schedule I or Schedule II controlled substance upon conviction is guilty of a Class D felony;
(2) Any other controlled substance, first offense or second offense, upon conviction is guilty of a Class A misdemeanor; and
(3) Any other controlled substance, third or subsequent offense, upon conviction is guilty of a Class D felony.
(c) For purposes of subsection (b) of this section, an offense is considered a third or subsequent offense if, before his or her conviction for the offense, the person has been convicted two (2) or more times for an offense under subsection (b) of this section or under any equivalent penal statute of the United States or of any state.