Iso: The New Synthetic Opioid That Is Causing Overdose Deaths

An addictive drug that — like fentanyl — is much more powerful than morphine is causing an increasing amount of overdose deaths across the United States.

Isotonitazene, commonly referred to as “iso,” is a synthetic version of etonitazene, an opioid that’s been around since 1957.

One report says the drug is causing about 40 to 50 deaths a month in the United States. That’s up from about six per month last summer.