Helping Patients Receive Safe and Effective Drug Therapy through Therapeutic Substitutions
In BC, pharmacists are able to provide therapeutic substitutions to help ensure patients receive safe and effective care (following the requirements under Professional Practice Policy-58: Medication Management (Adapting a Prescription).
Therapeutic SubstitutionsA therapeutic substitution is a type of prescription adaptation outlined in the College’s Professional Practice Policy for Medication Management (Adapting a Prescription). A pharmacist makes a therapeutic substitution when she/he substitutes the drug prescribed with a different drug that is expected to have a similar therapeutic effect, as long as that drug is from within the same therapeutic class. |
There are many instances when adapting an existing prescription is appropriate, such as during a drug recall or shortage, or to optimize a patient’s care. Adaptations always involve informed consent from the patient and notification to other health professionals on the patient’s care team.
The recent Health Canada recall of several drugs containing the active pharmaceutical ingredient valsartan is an excellent example of how pharmacists can use therapeutic substitutions to adapt prescriptions.
Valsartan RecallDrugs containing valsartan are used to treat patients with high blood pressure in order to help prevent heart attacks and stroke; as well as patients who have had heart failure or a recent heart attack. Patients affected need to continue to take their medications until they can safely transition to an alternative medication. Learn more. |
While situations like this are not common, when they do happen, pharmacists and other primary care providers need to work together with affected patients.
As a result of this recent recall, pharmacists are working with patients whose medication is affected to help them safely transition to an alternative medication. They are also collaborating with others on the patient’s care team as needed to ensure the alternative medication will maintain or enhance the effectiveness of the drug therapy and will not put the patient at increased risk.
Professional Practice Policy 58: Medication Management (Adapting a Prescription)
The College of Pharmacists of BC’s Professional Practice Policy - 58: Medication Management – Adapting a Prescription provides the framework to guide pharmacists in the safe and effective adaptation of existing prescriptions. This policy is applicable to pharmacists in all practice settings, including community, long-term care, hospital and other institutional pharmacy settings.
PPP-58 outlines that pharmacists may dispense a drug contrary to the terms of an existing prescription (adapt a prescription) if the action is intended to optimize the therapeutic outcome of treatment with the prescription drug; and all the following elements of a protocol to adapt a prescription have been met.
Protocol to adapt a prescription
Pharmacist has appropriate knowledge and understanding of the condition and the drug being dispensed in order to adapt the prescription.
Pharmacist has sufficient information about the specific patient’s health status to ensure that adapting the prescription will maintain or enhance the effectiveness of the drug therapy and will not put the patient at increased risk.
Pharmacist has a prescription that is current, authentic, and appropriate.
Pharmacist determines whether adapting the prescription is appropriate in the circumstances.
Pharmacist must obtain the informed consent of the client or client's representative before undertaking any adapting activity.
Pharmacist must document in the patient’s record any adaptation of the prescription, the rationale for the decision, and any appropriate follow-up plan.
Pharmacist must notify the original prescriber (and the general practitioner if appropriate) as soon as reasonably possible (preferably within 24 hours of dispensing) and this must be recorded in the patient’s record or directly on the prescription hard copy. |
Additionally, a pharmacist must also be satisfied that the following conditions are met when making a therapeutic substitution decision:
- The decision is in the best interest of the patient by:
- Addressing the health needs of that patient,
- Maintaining or enhancing the safety or effectiveness of drug therapy,
- Not placing the patient at increased risk,
- Considering formulary or payer restrictions and other patient-related information, and
- Ensuring the drug is approved for the intended indication by Health Canada or strong evidence supports using the drug for the intended indication (e.g., clinical practice guidelines);
- The pharmacist’s professional independence has been maintained and you avoid conflict of interest. If a decision is based on benefit to the pharmacist or pharmacy rather than the patient, this will be considered professional misconduct;
- You have considered all relevant information about the patient, the condition and the drug, and you have effectively communicated this to the patient to ensure they agree with the decision; and,
- You take full responsibility for your decision.
Pharmacists must be sure that adapting a prescription is appropriate for the patient under the current circumstances, and will, in their professional judgment, optimize the therapeutic outcome of treatment.
Therapeutic Substitutions and the Reference Drug Program
In most circumstances, therapeutic substitutions can only be applied to drugs that are a part of the Ministry of Health’s Reference Drug Program. Pharmacists may switch patients to another product within the Reference Drug Program Category if such a switch would be beneficial to the patient, allowable under PPP-58.
However, therapeutic substitutions are not limited to drugs included in the Reference Drug Program for practice settings such as hospital, long-term care facilities or multi-disciplinary environments where collaborative relationships or appropriate protocols are established.
Additional Resources
- Professional Practice Policy 58: Medication Management (Adapting a Prescription)
- PPP-58: Medication Management (Adapting a Prescription) Orientation Guide
- Orientation Guide - Declaration Form
- Pharmacist Prescription Adaptation Documentation and Notification Form
- Patient Inquiries About Renewals
- Brochure - Understanding Your Pharmacist's Role
- Decision Trees for Switching Drugs
- Reference Drug Program Updates are in Effect
- Drug Shortages in British Columbia: Information for Pharmacists
- Drugs containing valsartan being recalled due to contamination with potential carcinogen