A fact sheet is a plain-language explanation of the legislation that forms the foundation of certain pharmacy practices. It provides useful information and references to help pharmacy professionals understand a particular topic. A fact sheet is an informational resource and is not considered legal advice. Always refer to the legislation for full context.
Legislative References
Controlled Drugs and Substances Act, 1996
Additional References
- Code of Ethics
- Fact Sheet: Expiry Dates on Prescription Labels
Definitions
Controlled substance: A substance set out in Schedules I, II, III, IV, or Part 1 of V of the federal Controlled Drug and Substances Act, 1996 (CDSA). This resource specifically applies to the controlled substances named in Schedule 1 (narcotics), Schedule 2 (controlled drugs) and Schedule 3 (targeted substances) under the Controlled Substances Regulations.
Prescription drug: A drug on Health Canada’s Prescription Drug List and/or in NAPRA National Drug Schedule I.
Background
Pharmacists are required to determine whether it is appropriate to dispense a medication, whether a prescription is new or a refill. When an extended period of time has elapsed since a prescription was issued or last refilled, pharmacists have a professional and ethical responsibility to use their professional judgement, assess the patient, and consider the circumstances at hand to make a decision in the best interest of the patient.
Prescription Drugs
In Ontario, all prescriptions authorized by prescribers for prescription drugs remain valid, unless otherwise specified by the prescriber. While some pharmacy practice management systems may include a default pre-populated expiry date, this does not replace the pharmacist’s responsibility to exercise their clinical judgment and decision-making authority.
Controlled Substances
Prescriptions for controlled substances have additional requirements under federal legislation. Pharmacy professionals are required to document the date they receive the prescription (and their name).
The date a prescription is received is important because a prescription for a controlled substance is considered to “expire” two years from that date, rather than the date it was issued by the prescriber or dispensed. This receipt date also determines the period during which a pharmacist can adapt (modify) or renew (extend) the prescription, and during which a pharmacy professional can transfer it.
Health Canada will also accept the date the prescription was written as means to calculate the two-year period1. Deciding which date is most appropriate rests with the professional judgment of the pharmacist considering what is in the patient’s best interest and safety. If using the written date significantly shortens the prescription’s period of validity, the pharmacy professional should communicate this to the patient, along with the rationale, and document accordingly.
Published: October 2026
Version #: 2.1
Revision History
| Version # | Date | Action |
|---|---|---|
| 1.0 | June 2014 | Published as “Prescription Expiry Fact Sheet” |
| 2.0 | March 2020 | Added information on subsection 56 exemption from Health Canada. |
| 2.1 | October 2026 | Revised to reflect Controlled Substances Regulations coming into effect. |
1 Unless otherwise directed by the prescriber or specified on the prescription, an expiry date of October 1, 2028, may be used for any existing prescriptions received by the pharmacy prior to October 1, 2026 (Health Canada CS-GD-2022).