The main point: Overdose deaths continue to decline, but the drug supply continues to change, presenting new risks.

The details: Millennium Health released a report on drug use trends based on more than 1.69 million clinical urine drug tests collected 2016-2025.

The new data show the most sustained national decline in overdose deaths in two decades, but the continued rise of illicit stimulant use threatens to undercut progress.
Fentanyl + stimulants: In 2025, 85% of people testing positive for fentanyl also tested positive for an illicit stimulant, the highest proportion ever recorded in Millennium’s data. Illicit stimulant use increased among people using fentanyl in all U.S. Census regions 2024-2025. In 2025, for the first time, every state saw methamphetamine or cocaine detected more frequently than heroin or prescription opioids among people using fentanyl.
Stimulants: Stimulant use also rose in the absence of fentanyl, with methamphetamine detection among individuals not using fentanyl rising 4.5% in 2025 and cocaine detection rising 13.5%.
Fentanyl: There were significant drops in fentanyl detection 2023-2024, followed by a rapid rebound in late 2024-early 2025, mirroring overdose death data. A spike in heroin and other opioid detections in mid-2024 suggests a potential fentanyl supply shock.

The bigger picture: In addition to the fentanyl/stimulants combination, the illicit drug supply is changing to include other lethal combinations, including fentanyl with sedatives (e.g., xylazine, medetomedine, benzodiazepines) and novel synthetics.

Why it’s important: Policy, testing, and treatment have not caught up.

Lack of treatment: The Millennium report underscores the gap between the scale of stimulant use and the options available to treat stimulant use disorders. There are no FDA-approved medications to treat stimulant use disorders, and substantial barriers remain to contingency management, the most effective treatment available.
Complicated overdose response: Emergency overdose response can be more challenging for these polydrug combinations, as naloxone does not always work, and emergency workers may not know whether tranquilizers or stimulants are driving symptoms, for example.
Infections and wounds: Infectious diseases, severe wounds linked to xylazine, and stimulant-related cardiac crises are serious risks.
Lack of data: Forensic labs and coroners often lack resources to rapidly detect emerging compounds, meaning markets can shift months before data catches up.
Whack-a-mole approach: Targeting fentanyl alone without addressing the underlying demand for drugs incentivizes illegal drug suppliers to experiment with other compounds that bypass detection, creating a “whack-a-mole” cycle.