A massive survey recently released by a national drug-testing company strongly suggests we are well into the “fourth wave” of the opioid crisis.

The three previous waves were driven by 1. prescription opioids, 2. heroin, then 3. fentanyl. The fourth and current wave involves using opioids such as fentanyl combined with other lethal substances, including methamphetamines, cocaine, and xylazine (“tranq” or “tranq dope”).

These tragic findings don’t surprise me. I’m the chief medical officer of a large addiction treatment center based in Jacksonville, Florida, and we’ve seen polysubstance use—that’s, two or more drugs used at the same time or close in time—with our patients for a few years now.

The Millenium Health report is based on 4.1 million urine samples collected from people receiving drug addiction care between 2013 and 2023.

A key finding: Of the fentanyl-positive urine samples collected, 93 percent contained other illicit substances as well. More alarming still is that in the last year covered by the survey (2023), 60 percent of fentanyl-positive samples contained methamphetamine.

A potent, highly addictive stimulant that is fully capable of causing a lethal overdose all by itself, “meth” becomes even more dangerous and........

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