📅 CSA Calendar

Federal Law Notice

Pursuant to 21 CFR § 1306.04(a), a prescription for a controlled substance must be issued for a legitimate medical purpose by a practitioner acting in the usual course of professional practice. The responsibility for proper prescribing and dispensing of controlled substances is upon the prescribing practitioner, but a corresponding responsibility rests with the pharmacist who fills the prescription.

This "corresponding responsibility" doctrine means pharmacists have an independent duty to ensure controlled substance prescriptions are legitimate before dispensing. Early refills of controlled substances may indicate diversion, misuse, or a pattern inconsistent with legitimate medical use. Pharmacists must exercise professional judgment and may decline to fill prescriptions that raise red flags, including requests to fill controlled substances before the appropriate refill date.

This calculation is provided as a reference tool. Final dispensing decisions remain the professional responsibility of the pharmacist.