Mont. Code Ann. § 50-32-227

The board may except by rule any compound, mixture, or preparation containing any stimulant or depressant drug listed in 50-32-226 (1) and (2) from the application of all or any part of this chapter if the compound, mixture, or preparation contains one or more active medicinal ingredients not having a stimulant or depressant effect on the central nervous system and if the admixtures are included therein in combinations, quantity, proportion, or concentration that vitiate the potential for abuse of the drugs which have a stimulant or depressant effect on the central nervous system.