Md. Code, Criminal Law § 5–504

(a) Except when dispensed directly to an ultimate user by an authorized provider who is not a pharmacist, a controlled dangerous substance listed in Schedule III or Schedule IV that is a drug to which § 21–220 of the Health – General Article applies may not be dispensed without a written prescription, an electronic prescription, or an oral prescription.

(b) Unless renewed by the authorized provider, the prescription may not be:

(1) filled or refilled more than 6 months after the date of prescription; or

(2) refilled more than five times.