Small Study Suggests That Naltrexone Blockade Dose Not Block Ketamine Response

A small study at Yale demonstrated that treatment with naltrexone, an opioid-blocking agent used to treat alcohol use disorder, does not interfere with an antidepressant response to ketamine. Yoon, et al. followed 5 subjects being treated with naltrexone as they received ketamine infusions for depression. Three of five subjects showed remission, and 5/5 showed response. (See figure for details.)

This study contradicts an earlier one that showed no ketamine response for people under naltrexone blockage. More to come, I'm sure.

Recent data on opioids from the CDC

Study Shows Urban-Rural Split on Opioid Prescribing Rates; Putting the Numbers to Fentanyl Deaths in NYC

A new study just released from the CDC confirmed findings that opioid prescriptions were nearly twice as likely to occur among rural residents, compared to central metro areas. (García MC, Heilig CM, Lee SH, et al. Opioid Prescribing Rates in Nonmetropolitan and Metropolitan Counties Among Primary Care Providers Using an Electronic Health Record System — United States, 2014–2017. MMWR Morb Mortal Wkly Rep 2019;68:25–30. DOI: http://dx.doi.org/10.15585/mmwr.mm6802a1.)  The study analyzed data from the AthenaHealth electronic medical record system. This cloud based EMR is used by about 100,000 providers serving 86 million patients. De-identified data were used for the study.

The first take-home message is that there is a lot of opioid prescriptions flying out of rural providers’ offices. At the last data point in 2017, about 9% of patients in non-core and micropolitan areas, whereas only 5% received a prescription in central metropolitan areas.

A second major finding was that the percentage of patients in metro areas remained remarkably stable, at 5%, whereas in rural areas, it got as high as 10.3%, before starting to drop since 2016. 

The authors correctly point out that there are many possible reasons for such a finding. However, the split between rural and urban areas is solid.

In another article from the same issue (Colon-Berezin C, Nolan ML, Blachman-Forshay J, Paone D. Overdose Deaths Involving Fentanyl and Fentanyl Analogs — New York City, 2000–2017. MMWR Morb Mortal Wkly Rep 2019;68:37–40. DOI: http://dx.doi.org/10.15585/mmwr.mm6802a3,) deaths from fentanyl overdose increased dramatically. In 2012, about 2% of deaths involved fentanyl, but by 2017, fentanyl involvement was present in 57% of overdose deaths in New York City.

The CDC's Morbidity and Mortality Weekly is available to all here.