The time at which a prescription can be refilled is based on the discretion of the pharmacist and the guidelines given by the relevant state board of pharmacy, as explained by Dr. James L. Lindon in a Medscape article. The pharmacist may only dispense a refill for legitimate medical purposes.
Insurance policies may further limit the time at which a prescription may be refilled, as explained by insurance provider Aetna. For example, the North Carolina State Health Plan allows refills after 75 percent of the medication is used up. According to Rutland Pharmacy, an insurance provider may allow enrollees to refill prescriptions early if the subscriber plans to be out of town.