A nerve-blocking injection more commonly used to treat anxiety, PTSD, and certain pain conditions is now being tested directly against insomnia, and a new sham-controlled trial offers the first rigorously controlled look at whether it actually helps people sleep. The study, published in Nature and Science of Sleep, found a real but mixed signal.
What a Stellate Ganglion Block Is
The stellate ganglion is a cluster of nerves in the neck that forms part of the sympathetic nervous system — the branch of the body's autonomic wiring responsible for the "fight or flight" response. A stellate ganglion block (SGB) is an ultrasound-guided injection of local anesthetic directly onto this nerve cluster, temporarily dialing down that sympathetic signaling. It has an established track record as a treatment for conditions like complex regional pain syndrome and has drawn growing interest in recent years as an experimental treatment for PTSD and anxiety-linked sleep disturbance, on the theory that chronic insomnia is, in part, a disorder of nervous-system hyperarousal that won't switch off at night.
Until now, most of the evidence for SGB in insomnia specifically has come from small, uncontrolled pilot studies — the kind that can't rule out a placebo response. This trial was designed to close that gap.
How the Trial Was Designed
Researchers enrolled 72 adults with chronic insomnia disorder in a single-center, randomized trial. Every participant received the same base treatment: an ultrasound-guided stellate ganglion block once daily for 10 consecutive days. What differed between groups was an add-on treatment — press-needle therapy, a form of acupuncture-adjacent needling — which participants received either in its active form or as a closely matched sham version, allowing researchers to isolate the effect of the add-on itself.
Outcomes were tracked using both subjective sleep-quality questionnaires and objective, wearable-recorded total sleep time, along with standard screening scales for depression (PHQ-9) and anxiety (GAD-7).
A Split Result
Participants who received active press-needle therapy on top of the nerve block reported significantly greater short-term improvement in subjective sleep quality than those who received the sham version — the trial's primary positive finding. Depression scores improved more in the active-treatment group as well, while anxiety scores showed no significant difference between groups.
The picture was less clear-cut for objective sleep. Wearable-recorded total sleep time did show an overall difference between groups, but the more rigorous statistical test — whether the gap between groups widened over time as treatment progressed — did not reach significance. In plain terms, the device data couldn't confirm that people were measurably sleeping longer, even as they reported feeling like their sleep had improved. No serious adverse events occurred in either group.
That divergence between self-reported and device-measured results is a familiar pattern in sleep research, and the study's authors call for larger trials incorporating more robust objective sleep assessment, such as polysomnography, to resolve it.
Context From Related Research
This study arrives alongside a cluster of other recent SGB-insomnia research, underscoring both rising interest and the field's early stage. An earlier 2026 pilot study of a similar size had no sham arm at all, with its own authors cautioning that uncontrolled results shouldn't be read as evidence of efficacy until confirmed in sham-controlled work — exactly the gap this newer trial was designed to fill. A separate 2026 randomized trial compared two different anesthetics used in the SGB injection itself, a narrower question about procedural technique rather than whether the block works at all.
What This Means for Patients
Stellate ganglion block is not an approved, first-line insomnia treatment, and this trial — while a methodological improvement over earlier uncontrolled studies — is still small, single-center, and short-term. The gap between how much better people said they slept and what their wearables actually recorded is a meaningful caveat, not a footnote. Patients with chronic insomnia who haven't responded to standard options like cognitive behavioral therapy for insomnia (CBT-I) or approved medications should know this procedure exists and is being studied, but should treat it as investigational rather than a proven alternative. Anyone considering it should seek it through a clinical trial or a specialist familiar with the procedure's risks, which include the possibility of complications from an injection near major neck structures, rather than as an off-label quick fix.
