Non-opioid pain medications: What’s the lowest effective dose?

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Non-opioid pain medications: What’s the lowest effective dose?

An individual Portrait on prescribing the non-opioid pain medications gabapentin, pregabalin, and cyclobenzaprine was sent to approximately 6000 family doctors in BC. Physicians have been randomly divided into two groups to receive the Portrait at different times; the early group received a Portrait in February 2022 showing prescribing data from 2020, and the delayed group received a Portrait in January 2023 showing prescribing data from 2021. This Portrait was accompanied by Therapeutics Letter #134: Finding the lowest effective dose for non-opioid analgesics.

Abbreviations Used

BC: British Columbia
CPSBC: College of Physicians and Surgeons of British Columbia
EMR: electronic medical record
FP: family practitioner
GP: general practice
ICD: International Classification of Diseases
MSP: Medical Services Plan
PSP: Practice Support Program
RCMP: Royal Canadian Mounted Police

Sample Portrait

View a sample Portrait containing fictional individual physician data. You may also access the sample by clicking the DOWNLOAD button above. If you are a BC family physician and wish to sign up for (or opt out of) receiving Portrait, click on the REGISTER button above.

References and additional information

  1. Therapeutics Initiative. Finding the lowest effective dose for non-opioid analgesics. Therapeutics Letter. 2021 (Nov-Dec); 134:1-2.
  2. Therapeutics Initiative. Is cyclobenzaprine useful for pain? Therapeutics Letter. 2017 (Mar-Apr); 105:1-2.

Data definitions

Who received this Portrait?

BC physicians meeting all of the following criteria received an individual prescribing Portrait:

  • general practice (GP) physicians, including family practitioners (FP), who were registered by the BC Medical Services Plan (MSP) as having an active practice, or physicians registered primarily as GP-emergency medicine and FP-emergency medicine physicians; and
  • had a valid mailing address in BC according to the College of Physicians and Surgeons of British Columbia’s public physician information; and
  • had ≥100 prescriptions (for any drug) filled at a community pharmacy during the “Portrait period” (2020 or 2021) according to PharmaNet claims data; and
  • prescribed gabapentin, pregabalin, or cyclobenzaprine to at least 1 eligible patient in the Portrait period.

How were patients assigned to this Portrait?

Patients were included in a physician’s Portrait if they met all of the following criteria:

  • were continuously registered with the MSP during the Portrait period; and
  • were dispensed gabapentin, pregabalin, or cyclobenzaprine during the Portrait period, and the prescriber was the Portrait physician; and
  • were age ≥16 years at the time of dispensation; and
  • For patients treated with gabapentin or pregabalin, did not have a diagnosis of epilepsy (ICD9 345.X, ICD10 G40.X) in the 365 days before gabapentin or pregabalin dispensing, recorded in MSP fee-for-service claims, hospitalization records (discharge abstract database), or emergency room visits (the National Ambulatory Care Reporting System database).

Prescription data for patients who are federally insured (e.g. Veterans, RCMP, Armed Forces and beneficiaries of Non-Insured Health Benefits) or First Nations Health Benefits – PharmaCare Plan W were not included.

What prescriptions were included in this Portrait?

Filling events of gabapentin, pregabalin, or cyclobenzaprine prescriptions were extracted from PharmaNet claims data and included all prescriptions filled at a community pharmacy in BC with a physician’s prescribing number. Reversed prescription claims, out-of-province prescriptions, or drugs dispensed in hospital were not included.

How was daily dose calculated?

Daily dose for gabapentin, pregabalin, and cyclobenzaprine is based on the last prescription for each patient; therefore, each patient is presented once in each histogram. Daily dose was calculated by multiplying the number of tablets prescribed by the strength of the tablets, and dividing by days’ supply. Numbers were rounded to the closest integer (1 mg). If a patient had >1 prescription on the day of the last prescription, we summed the daily doses by drug. Note: patients who used multiple drugs during the Portrait period were included in multiple histograms.

Research component

The research objective is to determine the impact of the Portrait on physician prescribing. This impact will be evaluated at an aggregated level over the coming year by comparing pooled prescribing data from physicians in the early mailing group to pooled prescribing data from physicians in the delayed group. All prescribing data analyzed for this evaluation will not contain names, only encrypted patient and physician numbers. No physician or patient will be identified in any reports or publications. Portrait’s data access agreement requires the masking of data elements when <6 individuals (patients or physicians) are included. Ethics approval for this evaluation will be obtained from the University of British Columbia Clinical Ethics Review Board. This evaluation is being led by Drs. Colin Dormuth and Greg Carney, University of British Columbia, Faculty of Medicine, Department of Anesthesiology, Pharmacology, & Therapeutics.

If you have any questions or would like further information with respect to this evaluation, you may contact the Portrait team at (604) 822-4887 or email


Can I request the names of my patients included in this Portrait?

No. Portrait’s data access agreement only permits access to encrypted patient identifiers. There is no way for us to identify individual patients in the data or to provide you with a list.

However, other resources may be available for you. Contact your Practice Support Program (PSP) regional team to discuss how they might help you use your EMR to identify these patients.

I have a unique/specialized practice and do not believe that my data should be compared to GPs. Shouldn’t my comparison cohort be other physicians with practices similar to mine?

Our ability to accurately include physicians depends on how each physician is listed in the BC MSP data. For example, to be included in the program, a physician must be defined as a General Practitioner with a license status of Private Practice in the MSP data; beyond that, it is difficult to accurately identify any individual’s specific work environment, as many physicians work in multiple locations. We try to keep Portraits relevant to physicians by having a minimum prescribing criterion for each Portrait topic. Physicians who do not prescribe the drug in question or who write very few prescriptions for the drug typically will not receive a Portrait.

Creating accurate comparison cohorts is difficult for the same reasons. We often include the BC median as a point of interest when it is feasible, but we know that many physicians have unique or specialized practices and this comparator is not ideal. Hopefully, as we continue to build and refine the Portrait program, we will be able to provide comparisons that are more relevant to a variety of practices.

Portraits are really intended to be a tool for you to reflect upon and consider your own prescribing. Rest assured that we are not directly comparing your prescribing to any particular cohort. You are the only one who ever sees your own Portrait data, and you can decide for yourself whether you think your prescribing is in line with the evidence given your unique clinical setting. You will only receive future Portraits for which you have prescribed more than the minimum inclusion criteria, so you shouldn’t receive anything that is irrelevant to your practice.

Why does my Portrait show ranges of patients that I treated (1-20, 20-30, etc.), and not exact numbers?

Portrait’s data access agreement requires the masking of data elements when <6 individuals (patients or physicians) are included. As prescriptions are presented as percentages, we grouped the number of patients in order to mask low numbers of patients in each daily dose category.

I don’t see my question here. Where can I find more information?

Please check out our program FAQ section. We also welcome your feedback. Questions can be directed to our Portrait team by phone (604) 822-4887 or email


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