A retailer shall post notice at the location where a product containing pseudoephedrine or ephedrine as an active ingredient is displayed or offered for sale stating the following:
South Dakota law prohibits the sale or purchase of more than two packages containing pseudoephedrine or ephedrine as an active ingredient unless sold or purchased with a valid prescription drug order prescribed by a practitioner as defined in § 36-11-2 with appropriate authority.
SDCL 34-20D-5