Md. Code, Health Occupations § 12–501

(a) A pharmacist may refuse to dispense or refill a prescription if the decision is based on professional judgment, experience, knowledge, or available reference materials.

(b) (1) Except as provided in paragraph (2) of this subsection, if a pharmacist refuses to dispense or refill a prescription, the pharmacist shall, to the extent practicable, notify the authorized prescriber that the prescription or refill was refused within 72 hours after the refusal.

(2) Paragraph (1) of this subsection does not apply if a pharmacist is unable to determine the name of the authorized prescriber.