Blaise A. Algeo, of Newark, was arrested on Tuesday.
Troopers say that on Monday, the 22-year-old entered the First State Pharmacy at 1707 Foulk Road about 6 p.m.
Algeo was allegedly armed with a handgun and confronted two pharmacists to demand prescription medications.
The pharmacists gave him the medications and the he fled. No one was hurt.
Algeo has been charged with two counts of robbery and wearing a disguise during the commission of a felony.