Therapeutic Substitution – MAC Pricing for Proton Pump Inhibitors Effective February 1

Alberta Health’s move to Maximum Allowable Cost (MAC) pricing for eligible proton pump inhibitors (PPI) covered under government sponsored drug programs takes effect February 1, 2017. For details, please review Alberta Blue Cross Benefact 668 which also includes a patient information sheet to help you communicate this change.

MAC pricing introduces the need for therapeutic substitution for many individuals. This article provides limited guidance; solely for the purpose of pharmacists responding to Alberta Health’s MAC pricing policy for proton pump inhibitors. There are other limitations and considerations that must be considered in other situations.

Guidance for all Pharmacists

The Pharmacists and Pharmacy Technicians Regulation and related standards authorize pharmacists to “adapt a prescription from another prescriber by substituting another drug that is expected to have a similar therapeutic effect based on a patient assessment.” This type of adaptation should be limited to drugs within the same therapeutic class (i.e. proton pump inhibitors).

Pharmacists must use their professional judgment, and complete a patient assessment supported by clinical evidence to determine the appropriateness of therapeutic interchangeability. Standard 12(5)outlines considerations that pharmacists must make when determining if it is appropriate to adapt a prescription. For more information, please review the Chat, Check, Chart tools for assessment and documentation, and prescription adaptation.

Pharmacists must document in the patient’s record of care that the prescription was adapted, including the patient assessment and reference(s) used to support the prescribing decision. Pharmacists must communicate therapeutic substitution decisions to the original prescriber and any other relevant health professionals.

It is important to discuss substitution decisions with each patient, and receive their informed consent before substituting. Additionally, it is important that each patient be informed about indicators they should monitor that could result from the change in drug therapy.  

Limitations for Pharmacists Not Having Additional Prescribing Authority (APA)

Pharmacists not having APA must restrict adaptation practices to when they receive an original prescription (standard 12). This is interpreted to mean a new prescription. Therefore, subject to the above guidance, if a new prescription is received for a proton pump inhibitor, a pharmacist without APA may adapt the prescription to provide an alternative proton pump inhibitor. 

If a patient requires a refill of an existing prescription, authorization to therapeutically substitute must be sought and approved by an authorized prescriber. This may be the practitioner who originally prescribed the drug, or a member of the pharmacy team who has APA. However, if therapeutic substitution is authorized by another pharmacist having APA, that pharmacist must personally assess the patient, and the prescription must be authorized in their name. Substitution decisions must be patient specific; and, cannot be authorized through standing orders.