About.com states that the abbreviation "sig" is written before the directions on a prescription. "Sig" is an abbreviation for the Latin word "signetur," which means "let it be labeled."
In the area labeled "sig," the doctor directs how much medication to take, when to take the medication, how often to take the medication and how to use the medication. For example, the directions on a prescription could state: "Take one tablet by mouth two times a day with meals." According to About.com, other information contained on a prescription includes the name and dose of the medication, the amount of medication to dispense and the number of times to refill the medication.