ISO, the newest cause of opioid overdoses

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The relative scarcity of fentanyl on the illicit drug market, caused by China banning its production in August of 2019, has caused a new deadly drug to emerge Isotonitazine, known as ISO.

Category: Opioid Addiction

Table of Contents

What is ISO drug?

ISO is a derivative of etonitazene, a synthetic opioid first developed by pharmaceutical companies in the 1950s to treat pain. It is rarely used in the medical community because there are safer options.  ISO is highly potent and comes with dangerous side effects.

How dangerous is ISO drug?

ISO is believed to be more potent than fentanyl.

A recent article in U.S. News and World Report stated that ISO is causing 40 to 50 overdose deaths per month in the United States (up from about 6 per month in the summer of 2019). It has been detected in the blood of overdose victims in Indiana, Wisconsin and in our backyard in Illinois where, in some cases, it was mixed with cocaine.

The Drug Enforcement Administration (DEA) has now reclassified the potent synthetic opioid as a Schedule 1 drug with a high risk of abuse by users.

ISO is even more concerning to health practitioners because it is not easily detected in routine toxicology tests.

Some side effects of ISO can be:

  • Respiratory failure
  • Nausea
  • Vomiting

The potency of the ISO drug can also lead withdrawals worse than heroin withdrawal symptoms and more likely to experience withdrawal symptoms longer, known as opiate PAWS.

What does ISO look like?

ISO comes in the form of crystals or a white, off-white, or yellow powder that can be mixed with other substances (e.g., heroin, cocaine) or pressed into tablets.

Confiscated ISO drug - pills, powder, crystal

How do you stop ISO addiction?

Because ISO is an opioid, the same treatments that are effective for heroin or fentanyl addiction are the ideal choice for opioid addiction.  

The FDA-approved medications for opioid addiction are Suboxone, methadone and Vivitrol. Symetria offers all these and other medications with promising research. Though, the most common is Suboxone.

(See also the methadone vs. Suboxone article)

Suboxone in Illinois

Get quick access to Suboxone (Buprenorphine) anywhere across the Chicago metro.


Suboxone in Texas

Get fast access to Suboxone or related addiction or mental health medications in the Houston or Fort Worth areas.

Suboxone Fort Worth Area

Suboxone Houston Area

For more general education on treatment options, check out What is a Suboxone Clinic? and What is an IOP program?

 What do doctors think about ISO?

“Symetria Recovery has been quick to identify this new problem with ISO that is emerging and has completed internal education regarding ISO,” states Symetria Recovery Chief Medical Officer Dr. Andrew Giannotti. “Isotonitazene-related overdose deaths are on the rise both nationally, and even more so locally. Symetria has a large presence in Illinois, which is a state seeing one of the highest rates of ISO-related fatalities. This drug is the latest potent synthetic opioid to be manufactured and is giving rise to the same difficulties as Fentanyl. It is very lethal, being cut into a variety of other drugs unknowingly, not picked up on drug screens, and easily obtained on the dark web.  These qualities are a recipe for fueling another surge in the opioid epidemic.  Treatment professionals on the front lines of this battle need to be aware of the possibility that ISO is now available and being used by their patients.”

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Symetria has addiction treatment clinics across Illinois and Texas. You can likely get scheduled TODAY — medications or therapy.