The Cocodamol and Progabalin medication was taken from the Whithorn Pharmacy in St John Street sometime between last Saturday and Monday.
A window in the premises was smashed.
Police Scotland officers have been carrying out door to door enquiries and Constable Josh Maxwell said: “We want to hear from anyone who may have been in the vicinity of the pharmacy over the weekend to get in touch if they saw or heard anything suspicious. Under no circumstances should anyone take any medication which is not prescribed for them and we are appealing for anyone with any information about this crime to get in touch with us on the 101 number.”