It happened at 10:21 a.m. at Shepherdstown Pharmacy on 7670 Martinsburg Pike.
Sgt. Victor Lupis says the suspect displayed a firearm towards the employees, demanding prescriptions. He took an undisclosed amount.
They say the suspect is described as a white male, wearing a black ski mask, eye-glasses, a yellow sweatshirt and blue sweatpants.
Deputies say the suspect was between 5'9" and 5'10" with a thin build. They say he fled the scene in a black Pontiac Sunfire with a black convertible top.
They say he was last seen traveling west on Martinsburg Pike.
Anyone with information on this crime is asked to call the Jefferson County Sheriff's Department at (304)-728-3205.