Feds warn of increased use of dog tranquilizer in illegal fentanyl supply in the Northeast

BOSTON — Federal public health officials are warning the public about the illicit use of a dog tranquilizer in the illegal fentanyl supply in the Northeast.

Medetomidine increases the risk for overdose and severe withdrawal, the Centers for Disease Control and Prevention and the White House Office of National Drug Control Policy said in a joint statement on Thursday.

Medetomidine, also known as ‘rhino tranq,’ ‘mede,’ or ‘dex,’ is not approved for human use. It is approved for sedation and analgesia in dogs.

Medetomidine withdrawal can escalate quickly and result in dangerously high blood pressure and severe damage to the heart or brain, according to experts.

The federal health advisory for public health professionals, clinicians, laboratorians, and people at risk for overdose comes amid increasing reports of medetomidine in the illegal drug supply in the New England region and a severe withdrawal syndrome due to medetomidine exposure.

In July, local officials said Central and Western Massachusetts were found to have the highest levels of the veterinary sedative in the drug supply.

Health officials have said medetomidine may not respond easily to Narcan alone, and that the overdoses it causes are harder to reverse.

Medetomidine has been increasingly detected in law enforcement drug seizures, drug product and paraphernalia samples, and in wastewater samples, with the highest concentrations in the Northeast region, federal officials said.

Public health officials suspect that medetomidine is being synthesized in clandestine laboratories.

Medetomidine can cause profound sedation, bradycardia, and hypotension, experts said. Stopping medetomidine following regular use may lead to severe withdrawal, similar to clonidine withdrawal, with symptoms including hypertension, anxiety, nausea, vomiting, and fluctuating alertness, which can require emergency or intensive care.

Because fentanyl is involved in most overdoses involving medetomidine, opioid overdose reversal medications such as naloxone should be administered to restore normal breathing in suspected overdoses, officials said.

Federal officials said public health and public safety agencies, as well as clinicians, should collaborate to monitor the local drug supply and share timely information.

The CDC offered the following recommendations for people at risk for overdose:

• Carry naloxone and have a plan to use it by keeping it accessible, letting others know where it is, and calling 911 after administering it.
• Use drug test strips to detect substances in various drugs. Drug test strips are available for some substances, such as fentanyl, xylazine, and medetomidine. However, test strips can have false negative results, meaning the strip does not show the presence of a substance like fentanyl when in fact it is present in the product. Test strips also do not detect some fentanyl analogs (like carfentanil).
• Ask for help to address drug use. Addiction, also known as substance use disorder, is a treatable chronic condition. There are effective treatments, including medications for opioid addiction. To find treatment:
• Call or text 988
• Call SAMHSA’s helpline at 1-800-662-4357 for support or information on treatment and recovery
• Visit https://findtreatment.gov/
• Ask your doctor, or
• Go to an emergency department.
• Avoid mixing substances that have sedating effects, such as alcohol, benzodiazepines, opioids, or other sedating substances like medetomidine, because of increased overdose risk.
• Be alert for potential medetomidine withdrawal, which can escalate quickly and result in dangerously high blood pressure and severe damage to the heart or brain.
• Seek medical care for potential medetomidine withdrawal, which can escalate quickly and result in dangerously high blood pressure and severe damage to the heart or brain. Go to the hospital or call 911 if you:
• Can’t stop throwing up
• Have chest pain
• Are going in and out of awareness
• Are experiencing severe withdrawal symptoms

This is a developing story. Check back for updates as more information becomes available.

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