Colorado sleep aid sales dropped sharply when recreational cannabis dispensaries opened nearby | Research

The takeaway

Over-the-counter sleep aid market share declined 236% from its growth trend after recreational cannabis dispensaries opened in Colorado counties, suggesting widespread substitution of cannabis for conventional sleep medications.

People who use cannabis for sleep, those interested in cannabis substitution effects, and anyone following cannabis legalization impacts.

236% reversal in sleep aid market share growth after dispensary entry

What the researchers found

Sleep aid market shares were growing before recreational cannabis availability, but the trend reversed with dispensary entry (-0.33 percentage points from a mean growth of 0.14). The decline increased with more dispensaries and higher county-level cannabis sales, and was driven by diphenhydramine and doxylamine products rather than herbal or melatonin supplements.

Why it matters

Sleep disturbances are not a qualifying condition under any US medical cannabis law, yet this data shows people are already substituting cannabis for OTC sleep aids at scale. This gap between actual use and regulatory recognition has implications for both policy and clinical research.

The numbers in context

236% decrease in sleep aid market share growth trend after dispensary entry. -0.33 percentage point shift (95% CI: -0.43 to -0.24, p < 0.01) from mean growth of 0.14. Effect size increased with dispensary count and sales volume. Driven by diphenhydramine/doxylamine products, not melatonin.

How the study worked

Multivariable panel regression using UPC-level grocery store scanner data comparing monthly sleep aid market shares against dispensary access (existence, sales, count) across Colorado counties between December 2013 and December 2014.

What this study cannot tell us

Ecological study design cannot confirm individual-level substitution. Only covers one year of data in one state. Scanner data from grocery stores may not capture all OTC sleep aid purchases. Cannot determine whether cannabis is equally or more effective than OTC sleep aids.

How to read the evidence

Moderate: rigorous econometric analysis with large dataset and multiple controls, but ecological design.

When this study was published

Published in 2019, using 2013-2014 data.

The bigger picture

This is real-world market data showing large-scale behavior change. People are voting with their wallets, choosing cannabis over drugs like Benadryl and Unisom for sleep. This calls for comparative effectiveness research rather than just more surveys about preferences.

Questions still open

Is cannabis actually more effective than diphenhydramine or doxylamine for sleep? Why was melatonin not affected by the substitution? What are the comparative side effect profiles of cannabis versus OTC sleep aids for long-term use?

Common questions

Are people replacing sleep pills with cannabis?

This study found strong evidence of substitution in Colorado. When recreational dispensaries opened, sales of antihistamine-based sleep aids like Benadryl and Unisom dropped significantly, while melatonin and herbal products were unaffected.

Is cannabis better for sleep than OTC sleep aids?

This study measured purchasing behavior, not effectiveness. It shows people are choosing cannabis over OTC sleep aids, but comparative clinical trials are needed to determine which option is safer and more effective.

Read the original research

Using recreational cannabis to treat insomnia: Evidence from over-the-counter sleep aid sales in Colorado.

Complementary therapies in medicine, 47, 102207

View on PubMed ↗Publisher’s paper ↗

Citation

Doremus, Jacqueline M; Stith, Sarah S; Vigil, Jacob M. (2019). Using recreational cannabis to treat insomnia: Evidence from over-the-counter sleep aid sales in Colorado.. Complementary therapies in medicine, 47, 102207. https://doi.org/10.1016/j.ctim.2019.102207