C.R.S. § 18-18-206: Schedule IV.

(1) A substance shall be added to schedule IV by the general assembly when:

(a) The substance has a low potential for abuse relative to substances included in schedule III;

(b) The substance has currently accepted medical use in treatment in the United States; and

(c) The abuse of the substance may lead to limited physical dependence or psychological dependence relative to the substances included in schedule III.

(2) Unless specifically excepted by Colorado or federal law or Colorado or federal regulation or more specifically included in another schedule, the following controlled substances are listed in schedule IV:

(a) Any material, compound, mixture, isomers or salts or isomers, or preparation containing any of the following narcotic drugs, or their salts calculated as the free anhydrous base or alkaloid, in limited quantities as follows:

(I) Not more than 1 milligram of difenoxin and not less than 25 micrograms of atropine sulfate per dosage unit;

(II) Propoxyphene (dosage forms);

(III) Butorphanol;

(b) Any material, compound, mixture, or preparation containing any quantity of the following substances having a depressant effect on the central nervous system, including any salts, isomers, and salts of isomers of them that are theoretically possible within the specific chemical designation:

(I) Alprazolam;

(II) Barbital;

(III) Bromazepam;

(IV) Camazepam;

(V) Chloral betaine;

(VI) Chloral hydrate;

(VII) Chlordiazepoxide;

(VIII) Clobazam;

(IX) Clonazepam;

(X) Clorazepate;

(XI) Clotiazepam;

(XII) Cloxazolam;

(XIII) Delorazepam;

(XIV) Diazepam;

(XV) Estazolam;

(XVI) Ethchlorvynol;

(XVII) Ethinamate;

(XVIII) Ethyl loflazepate;

(XIX) Fludiazepam;

(XX) Flunitrazepam;

(XXI) Flurazepam;

(XXII) Halazepam;

(XXIII) Haloxazolam;

(XXIV) Ketazolam;

(XXV) Loprazolam;

(XXVI) Lorazepam;

(XXVII) Lormetazepam;

(XXVIII) Mebutamate;

(XXIX) Medazepam;

(XXX) Meprobamate;

(XXXI) Methohexital;

(XXXII) Methylphenobarbital (mephobarbital);

(XXXIII) Midazolam;

(XXXIV) Nimetazepam;

(XXXV) Nitrazepam;

(XXXVI) Nordiazepam;

(XXXVII) Oxazepam;

(XXXVIII) Oxazolam;

(XXXIX) Paraldehyde;

(XL) Petrichloral;

(XLI) Phenobarbital;

(XLII) Pinazepam;

(XLIII) Prazepam;

(XLIV) Quazepam;

(XLV) Temazepam;

(XLVI) Tetrazepam;

(XLVII) Triazolam;

(XLVIII) Zolpidem;

(c) Repealed.

(d) Any material, compound, mixture, or preparation containing any quantity of the following substances having a stimulant effect on the central nervous system, including their salts, isomers, and salts of isomers:

(I) Cathine;

(II) Diethylpropion;

(III) Fencamfamin;

(IV) Fenpropore;

(V) Mazindol;

(VI) Pemoline (including organometallic complexes and chelates thereof);

(VII) Phentermine;

(VIII) Pipradrol;

(IX) SPA ((-)-1-dimethylamino-1,2-diphenylethane);

(e) Any material, compound, mixture, or preparation containing any quantity of the following substances, including their salts and isomers:

(I) Modafinil;

(II) Pentazocine;

(III) Sibutramine;

(IV) Stadol (butorphanol tartrate);

(f) Zaleplon.

(3) The board may exempt by rule any compound, mixture, or preparation containing any depressant substance listed in paragraph (b) of subsection (2) of this section from the application of all or any part of this article if the compound, mixture, or preparation contains one or more active medicinal ingredients not having a depressant effect on the central nervous system, and if the admixtures are in combinations, quantity, proportion, or concentration that vitiate the potential for abuse of the substances having a depressant effect on the central nervous system.