- First-time amphetamine/dextroamphetamine prescription rates remained stable overall, but increased significantly for people 30-44, 45-64, and 65+ years of age.
- The percentage of prescriptions filled within 5 days of being written reached their lowest values in March 2023, a decrease of 10.6 percentage points, compared to the three months before the shortage started.
In October 2022, the US Food and Drug Administration (FDA) announced a shortage of a combination of amphetamine and dextroamphetamine drugs commonly found in Adderall and used to treat ADHD and narcolepsy (US Food & Drug Administration, 2022). We’ve previously explored rates of prescription fills over time within a population of people who would be eligible to receive the drug (i.e., people who have received a dispense of the drug within the prior two years). We’ve also previously shown increases in the rate of first-time ADHD diagnoses overall and specifically for people over 30 years old since 2021.
The FDA cites an increase in demand as the reason for the continued shortage (US Food & Drug Administration, 2023). Building upon our previous analysis and in partnership with The Wall Street Journal, we were curious to understand if there were increases in first-time amphetamine/dextroamphetamine prescriptions that may have contributed to the increase in demand. If there were, we were curious to understand which age groups experienced the largest increases. Further, of the people who did receive a prescription for amphetamine/dextroamphetamine, we were curious to understand if they received their prescription within 5, 10, or 30 days and how this rate may have changed since the shortage began (we will henceforth refer to this as a prescription fill).
You can explore this study directly within Truveta Studio.
Methods
We conducted two independent analyses:
- We looked at changes over time in the rate of first-time amphetamine/dextroamphetamine prescriptions.
- We also explored the prescription fill rate for amphetamine/dextroamphetamine prescriptions.
First-time amphetamine/dextroamphetamine prescriptions
We included a population of people who had an encounter within the previous two years. We calculated the monthly rate of first-time amphetamine/dextroamphetamine prescriptions per 10,000 eligible people between January 2021 and October 2024. People were eligible if they had no prior evidence of amphetamine/dextroamphetamine prescription and they had an encounter with the health system in the prior two years.
Rates were calculated overall and for seven age groups (0-11 years old, 12-14 years old, 15-17 years old, 18-29 years old, 30-44 years old, 45-64 years old, and 65+ years of age). Linear regression models were used to test for changes over time.
Amphetamine/dextroamphetamine prescription fill rate
We looked at the percent of amphetamine/dextroamphetamine prescriptions that were filled between January 2020 and May 2024. We included a population of people who had prescriptions for amphetamine/dextroamphetamine between January 2020 and May 2024. Patients were required to have evidence of a prescription fill of any drug at any time. Truveta receives prescription fill data from the member health systems in addition to traditional EHR data.
We calculated the rate of prescriptions that were filled within 5, 10, or 30 days of when the original prescription was written. The rate was defined as the number of prescriptions that were written and filled within 5, 10, or 30 days (numerator) per the number of prescriptions that were written (denominator). If a patient had multiple prescriptions within one calendar month, only one was included in this analysis. This analysis was conducted for first-time prescriptions and for all prescriptions.
Results
Rate of first-time amphetamine/dextroamphetamine prescriptions
We found 520,408 people with first-time amphetamine/dextroamphetamine prescriptions during the study period. Overall, we did not see an increase in the rate of first-time of amphetamine/dextroamphetamine prescriptions per 10,000 eligible people across the study period. Starting in the summer of 2024, we saw a decrease in the rate of first-time amphetamine/dextroamphetamine prescriptions.
When stratifying by age group, we observed increases in the rate of first-time prescriptions for all age groups over 30 years of age (p≤0.001). The largest increases were seen in the 30-44-year-old age group (0.04 new prescriptions per month per 10,000 eligible people).
For two of the younger age groups, there were small, but significant decreases in the rate of first-time amphetamine/dextroamphetamine prescriptions across the study period (15-17-year-olds: -0.03, p = 0.005 and 18-29-year-olds: -0.02, p = 0.04).
First-time prescription fill rates
The percentage of first-time prescriptions filled reached a relative peak in October 2022 at 66.9%, 70.1%, and 74.7% prescriptions filled per those written within 5, 10, and 30 days, respectively. The percentage of first-time prescriptions filled within all timeframes began to decrease in November 2022. Compared to three months prior to the shortage start (August – October 2022), in the three months after the shortage began (November 2022 – January 2023), first-time prescription fill rates had decreased by 6.3, 5.2, 5.9 percentage points within 5, 10, and 30 days, respectively.
However, the percentage of first-time prescriptions filled reached their lowest rate in March 2023; only 53.7% of first-time prescriptions were filled within 5 days of being written. The February, March, and April 2023 average fill rate within 5 days decreased by 14.5 percentage points compared to the three months prior to when the shortage began. This trend was similar for first-time prescriptions filled within 10 and 30 days as well; first-time prescriptions filled within 10 days decreased by 13.1 percentage points to a rate of 57.0% in March 2023, and prescriptions filled within 30 days decreased by 11.1 percentage points to a rate of 64.5% in March 2023.
Overall prescription fill rates
Although the overall fill rate was higher than the first-time first rate, we observed similar time trends across both analyses.
For the overall population, relative peak fill rates were seen in October 2022 (fills within 5 days: 69.5%, fills within 10 days: 76.6%, and fills within 30 days: 88.5%).
The lowest fill rates within 5- and 10-days were seen in March 2023; the mean rate of prescriptions filled within 5- and 10-days during February, March, April 2023 decreased by 10.6 and 7.8 percentage points compared to three months prior to the shortage, respectively.
The fill rate within 30 days reached a minimum in January 2023 and decreased by 3.8 percentage points compared to three months prior to the shortage.
Following this decrease in prescription fill rates, rates began to increase again.
Discussion
In this analysis, we built upon our previous understanding of the amphetamine/dextroamphetamine shortage, but added details for first-time prescription rates and the percentage of prescriptions that are getting filled. Although we don’t see increases in the rate of first-time prescriptions overall, all populations over the age of 30 experienced significant increases in the rate of first-time prescriptions. Previous reports have highlighted this after the pandemic (Danielson et al., 2023), but the recency of these data showcase that these trends may be continuing. The raw data also show a slight decrease in the rate of first-time prescriptions since the summer of 2024. Additional research is needed to understand what may be contributing to these decreases and specifically if people are receiving other prescriptions/medications given the amphetamine/dextroamphetamine shortage.
Although the amphetamine/dextroamphetamine shortage was reported to start in October 2022, we did not see substantial decreases in the rate of prescription fills for a few months. We saw the lowest rates in prescription fills in March 2023. Prescriptions filled within 10 days had the greatest percent decrease (compared to prescriptions filled within 5 and 30 days). This may indicate that many people were still able to access their medication; however, it took longer to find pharmacies that had the medications in stock. However, given the decreases especially in the spring of 2023, our data suggests people were either delayed or prevented from receiving their amphetamine/dextroamphetamine prescriptions. Fill rates have stabilized to pre-shortage rates, either indicating people are able to fill the prescription or new prescriptions for amphetamine/dextroamphetamine have decreased.
There are a few limitations associated with this analysis. First, in this analysis, the data are based on prescription rates; if a patient did not receive a prescription because they were aware of the shortage and did not seek a prescription, this would not be captured in this analysis. Further, if a patient received a prescription for an alternative drug due to the shortage, we did not capture that here. Additionally, we describe increases in amphetamine/dextroamphetamine prescriptions in general; these prescriptions are approved for people with either ADHD or narcolepsy (US Food & Drug Administration, 2023). We did not distinguish between the two conditions in this analysis. Further, Truveta Data is electronic health record data collected as part of clinical care. During the shortage if patients became discouraged and sought out non-traditional methods to receive prescriptions, such as via telehealth companies, our analysis would not capture this. We did not require that patients previously received care within a Truveta member health care system. Additionally, in the prescription analyses, we did not take into account previous medication dispense history. However, even with these limitations, this analysis sheds additional light on some of the contributing factors to the shortage.
These are preliminary research findings and not peer reviewed. Data are constantly changing and updating. These findings are consistent with data accessed on Nobember 13, 2024.
Citations
Danielson, M. L., Bohm, M. K., Newsome, K., Claussen, A. H., Kaminski, J. W., Grosse, S. D., Siwakoti, L., Arifkhanova, A., Bitsko, R. H., & Robinson, L. R. (2023). Trends in Stimulant Prescription Fills Among Commercially Insured Children and Adults—United States, 2016–2021. MMWR. Morbidity and Mortality Weekly Report, 72(13), 327–332. https://doi.org/10.15585/mmwr.mm7213a1
US Food & Drug Administration. (2022). FDA Drug Shortages (Current and Resolved Drug Shortages and Discontinuations Reported to FDA – Amphetamine Aspartate Monohydrate, Amphetamine Sulfate, Dextroamphetamine Saccharate, Dextroamphetamine Sulfate Tablet). https://www.accessdata.fda.gov/scripts/drugshortages/dsp_ActiveIngredientDetails.cfm?AI=Amphetamine%20Aspartate%20Monohydrate,%20Amphetamine%20Sulfate,%20Dextroamphetamine%20Saccharate,%20Dextroamphetamine%20Sulfate%20Tablet&st=c
US Food & Drug Administration. (2023). FDA Announces Shortage of Adderall. https://www.fda.gov/drugs/drug-safety-and-availability/fda-announces-shortage-adderall