News Release

Tuesday, March 2, 2021

Law enforcement seizures of methamphetamine and marijuana rose during pandemic

An analysis of law enforcement seizures of illegal drugs in five key regions of the United States revealed a rise in methamphetamine and marijuana (cannabis) confiscations during the COVID-19 pandemic. Seizures of the two drugs were higher at their peak in August 2020 than at any time in the year prior to the pandemic. While investigators found that trends in heroin, cocaine and fentanyl seizures were not affected by the pandemic, provisional overdose death data show that the increased drug mortality seen in 2019 rose further through the first half of 2020. 

The findings suggest that the pandemic and its related restrictions may have impacted the availability and demand of some, but not all, illegal drugs, and that availability may have increased in summer and fall of 2020 in the five regions included in this study.

The study, published today in Drug and Alcohol Dependence, was supported by the National Institute on Drug Abuse (NIDA), part of the National Institutes of Health.

“At the beginning of the pandemic, it was unclear how social distancing, travel restrictions and economic hardship in communities would impact drug supply and demand,” said Nora D. Volkow, M.D., NIDA director. “Drug seizure data like these give us additional insight into the changing drug use landscape during COVID-19 and may inform our understanding of rising rates of methamphetamine- and opioid-involved overdose deaths during the pandemic.”

Measures to address the COVID-19 pandemic have limited social gatherings, closed international borders, and reduced economic activity across many sectors. While provisional data reveal drug overdose deaths have risen during the pandemic, there is little scientific evidence to illuminate the impact of these measures on drug availability and use in the United States.

Seeking answers, investigators led by Joseph J. Palamar, Ph.D., M.P.H., associate professor at the New York University Grossman School of Medicine and co-investigator on the National Drug Early Warning System (NDEWS), mined data on drug seizures by law enforcement. The data were collected through the High Intensity Drug Trafficking Areas program, a grant program aimed at reducing drug trafficking and misuse administered by the Office of National Drug Control Policy in which the Drug Enforcement Administration and the Centers for Disease Control and Prevention play an active role.

Drug seizure data from March 2019 through September 2020 was analyzed in five key U.S. regions: Washington, D.C./Baltimore, Chicago, Ohio, New Mexico, and North Florida. Investigators analyzed 29,574 seizures of five drugs: marijuana, methamphetamine, fentanyl, heroin, and cocaine.

Incidences of marijuana and methamphetamine seizures dipped at the beginning of the pandemic, with low points in April 2020. But confiscations of both substances subsequently rose, exceeding pre-COVID-19 seizure rates and reaching their peaks in August 2020. The quantities of marijuana seized, measured by weight, also climbed significantly from April through September 2020.

While decreases in seizures can indicate decreases in drug availability in communities, it is also possible that decreases may indicate reduced law enforcement during the early months of the pandemic. Study authors noted that it remains unknown if the high post-COVID-19 seizures represent greater drug availability, or whether law enforcement officials were merely ‘catching up’ regarding previous months of delayed seizures.   

Investigators found no significant shifts in the pattern of fentanyl, cocaine, or heroin seizures since the onset of COVID-19, although they emphasize fentanyl seizures have continued to rise steadily from March 2019 through September 2020 irrespective of the pandemic.

“Our understanding of how the COVID-19 pandemic affects drug use is evolving, but we do know that social isolation, even for short periods, can cause psychological distress that may drive some people to seek out psychoactive substances,” said Dr. Palamar. “It is critical for us to obtain a clearer picture of how the pandemic has influenced drug supply and demand, so that we may better mitigate potential harmful effects of changing drug use patterns.”

The researchers emphasize drug seizure rates are only rough measures of drug availability and use and that additional research is needed to understand how individuals’ drug use may be changing during the pandemic. These are critical public health questions, as changes in an individual’s drug use—such as abruptly stopping a certain substance or switching to a different one—can increase the chance of drug-related harm, such as withdrawal or overdose. Additionally, further research is needed to assess if patterns observed in these key U.S. regions extend to other parts of the country.

Overdose deaths involving methamphetamine started rising steeply in 2009, and provisional numbers from the CDC show overdose deaths involving stimulant drugs, including methamphetamine, have increased 39% in the year ending in June 2020 compared to the year ending in June 2019. Previous research has found that methamphetamine use has increased significantly among people with an existing opioid use disorder and has disproportionately impacted certain racial and ethnic communities, especially American Indians/Alaska Natives.

This work was supported by NIDA’s National Drug Early Warning System (U01DA051126 and R01DA044207).

About the National Institute on Drug Abuse (NIDA): NIDA is a component of the National Institutes of Health, U.S. Department of Health and Human Services. NIDA supports most of the world’s research on the health aspects of drug use and addiction. The Institute carries out a large variety of programs to inform policy, improve practice, and advance addiction science. For more information about NIDA and its programs, visit

About the National Institutes of Health (NIH): NIH, the nation's medical research agency, includes 27 Institutes and Centers and is a component of the U.S. Department of Health and Human Services. NIH is the primary federal agency conducting and supporting basic, clinical, and translational medical research, and is investigating the causes, treatments, and cures for both common and rare diseases. For more information about NIH and its programs, visit

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J Palamar et alShifts in drug seizures in the United States during the COVID-19 pandemicDrug and Alcohol Dependence DOI: 10.1016/j.drugalcdep.2021.108580 (2021).