TO: Registered Pharmacists
FROM: Grant Carrow, Ph.D.
Director, Drug Control Program
DATE: July 23, 1997
RE: Policy on Drug Interchangeability and Midstream Interchange
In order to address public health concerns regarding drug product selection, the Department of Public Health has revised and clarified definitions and policy on midstream interchange (formerly referred to as "midstream substitution"). Attached, please find a copy of the revised policy which supersedes previous policy.
Pharmaceutical and medical expertise at state and federal levels continues to ensure that safe and effective equivalent drug products are available to consumers. However, pharmacists and prescribers must be able to respond to other individual consumer needs. The revised policy strengthens the Department's commitment to increased communication among the patient, prescriber and pharmacist while maintaining the goal of access to affordable drug therapy.
In order to clarify the regulations concerning drug interchange, the Department plans to incorporate the definitions and principles of this policy in revisions to the regulations. Nevertheless, the policy is consistent with current authority and should be followed in the interim.
If you have any questions, please do not hesitate to contact the Drug Control Program at (617) 983-6700.
Policy on Drug Interchangeability and Midstream Interchange
This policy sets forth, in accordance with M.G.L. c. 17, § 13, M.G.L. c. 112, § 12D and 105 CMR 720.000, procedures for (a) determining the effective date on which a drug product is interchangeable; and (b) initiating a midstream interchange when a drug product is no longer sole source. The policy revises and clarifies key definitions and supersedes previous Department policy on midstream interchange (formerly referred to as "midstream substitution" for prescription refills).
Midstream interchange means the first time an interchangeable drug product is dispensed pursuant to a prescription written prior to the date of listing on which the drug changed from sole source to multi-source.
Date of listing means the date on which a drug product listing first appears in print in the Massachusetts List of Interchangeable Drugs. Said date is:
- for drug products listed pursuant to 105 CMR 720.050(a), the date the edition or supplement of the Approved Drug Products with Therapeutic Equivalence Evaluations (Orange Book) is postmarked or posted electronically, whichever is first, by the United States Department of Health and Human Services;
- for drug products listed pursuant to 105 CMR 720.050(b), the date the Additional List is published by the Secretary of State in the Massachusetts Register; or
- for drug products listed pursuant to 105 CMR 720.080, the date the Exception List is published by the Secretary of State in the Massachusetts Register.
Effective date of interchangeability means not later than 90 days after the date of listing of a drug product in the Massachusetts List of Interchangeable Drugs.
II. Drug Interchangeability
According to Massachusetts law, pharmacists must dispense a less expensive, reasonably available, interchangeable drug product provided that (a) the drug product is listed in the Massachusetts List of Interchangeable Drugs (MLID) and (b) the prescriber has not indicated "no substitution". A pharmacist shall interchange accordingly when dispensing a new prescription or a prescription refill presented after the effective date of interchangeability.
III. Midstream Interchange
With respect to midstream interchange, open communication among pharmacist, patient, and prescriber is important because there may be factors other than bioequivalence or interchangeability, including patient concerns, that may affect drug product selection. Therefore, a pharmacist presented with a new prescription or prescription refill that requires midstream interchange shall notify the patient and prescriber of said requirement in those cases in which such notification is, in the pharmacist's professional judgment, reasonably indicated for the proper care of the patient. Such notification may be written or oral and may be conveyed by telephone, facsimile, electronic transmission or other approved means. To prevent a midstream interchange, the prescriber must issue a new prescription that indicates "no substitution".
The above policy permits a pharmacist up to 90 days after a drug product is published as interchangeable to put into effect the requirement for interchange. This affords pharmacists the time to continue filling the prescription as originally dispensed while making the necessary administrative changes and communicating with patients and prescribers. There is no requirement to wait the full 90 days to initiate an interchange.
Communication with patient and prescriber may be particularly important for interchange on prescriptions written prior to the date of listing of a drug that has changed from sole source to multi-source. In such cases, called midstream interchange, the prescriber and patient may not have been aware at the time the prescription was written that the drug would become multi-source and interchangeable. This applies whether the change to ongoing drug therapy occurs at the filling of a new prescription or refill.
Publication of the MLID serves as public notification of the requirement for interchange, but is not patient specific. Therefore, the pharmacist must use professional judgment to determine whether there is a need to communicate about the midstream interchange with prescriber and patient. Once notification is provided, there is no requirement for an acknowledgment or response from the patient or prescriber. However, a prescriber may at any time issue a new prescription that indicates "no substitution". A copy of the notification or a notation that it was provided should be maintained in the pharmacy record.
For further information, please contact the Drug Control Program at (617) 983-6700.
This information is provided by the Drug Control Program within the Department of Public Health.