(a) A controlled dangerous substance listed in Schedule V may not be distributed or dispensed except for a medical purpose.

(b) When dispensing the controlled dangerous substance, an authorized provider shall securely affix to the container, in addition to any other label already there, a label with:

(1) the dispenser’s name, signature, and registry number;

(2) the date on which the controlled dangerous substance is dispensed; and

(3) the purchaser’s name.