Auricular Acupuncture Treatment for Insomnia: A Systematic Review

Insomnia is an extremely common condition that affects millions of people worldwide, characterized by difficulty falling asleep, maintaining sleep, waking up too early, or experiencing poor-quality sleep. Global studies show that about 16% of people have difficulty falling asleep, while 25% report problems maintaining sleep or waking up prematurely. In the United States, more than half of the population experiences at least one symptom of insomnia several nights per week. In addition to nighttime discomfort, insomnia causes daytime sleepiness, irritability, depression, and impaired social and occupational functioning, generating economic costs estimated at $30 to $35 billion annually in the United States alone.

In this context, auricular acupuncture — a technique that stimulates specific points on the external ear — has attracted growing interest as a therapeutic alternative. Developed in the 1950s, this technique uses various methods such as needles, medicinal plant seeds, and magnetic beads to stimulate specific points on the ear, and is considered an economical and effective treatment with few adverse effects.

The objective of this study was to systematically evaluate the efficacy and safety of auricular acupuncture in the treatment of insomnia, in addition to identifying which ear points are most commonly used by therapists. To this end, the researchers conducted a comprehensive search of international and Chinese medical databases, looking for randomized controlled clinical trials that tested auricular acupuncture as the sole treatment for insomnia. Only studies that compared auricular acupuncture with no treatment, placebo, sham auricular acupuncture, or conventional medications were included. Two independent reviewers analyzed the data extracted from the studies, evaluating the methodological quality according to rigorous criteria and performing statistical analyses to combine the results from the different studies.

Efficacy was measured primarily through the recovery and symptom improvement rates reported by patients.

Of the 878 scientific articles initially found, only six studies met the inclusion criteria, involving a total of 673 participants, of whom 402 received auricular acupuncture. Five studies were conducted in mainland China or Hong Kong, and all compared auricular acupuncture with conventional medications or routine care. The combined analysis of the results showed that auricular acupuncture was significantly more effective than the controls, with patients showing higher rates of recovery and improvement of insomnia symptoms. When compared specifically with diazepam, a medication commonly used for insomnia, auricular acupuncture also demonstrated statistical superiority.

The studies that evaluated sleep duration showed that auricular acupuncture was more effective in helping patients sleep at least six hours per night, with better sleep maintenance and a sense of restfulness upon waking. Interestingly, when the researchers analyzed different types of auricular stimulation, they found that the use of seeds from the Vaccaria segetalis plant was statistically superior to controls, while magnetic beads did not show significant differences.

For patients suffering from insomnia, these results suggest that auricular acupuncture may be a promising therapeutic option, especially considering that many prefer to avoid sleep medications because of their potential side effects and risk of dependence. The study identified six most commonly used auricular points: Shenmen, which was used in 100% of the studies, followed by Heart, Occiput, Subcortex, Brain, and Kidney. These specific points can serve as a guide for clinicians who wish to apply the technique. For practitioners, the results indicate that auricular acupuncture, particularly using Vaccaria seeds, can be incorporated as part of the therapeutic arsenal for insomnia.

The technique appears to be especially useful for helping patients achieve at least six hours of continuous sleep, which is considered an important milestone for the quality of nighttime rest.

However, it is essential to recognize the significant limitations of this study. All six studies analyzed were classified as being of low methodological quality, mainly because none of them adequately described how the randomization of participants was carried out, a process that is crucial to ensure reliable results. In addition, no study used adequate blinding techniques, which may have influenced the results, since both patients and practitioners knew which treatment was being applied. Most studies also did not report clear inclusion and exclusion criteria for patients, nor did they use standardized and validated tools to measure improvement in insomnia.

Of concern, only one study reported information on participant dropouts during treatment, and none mentioned possible adverse effects of auricular acupuncture, limiting our understanding of the safety of the treatment. The duration of the studies was generally short, and only one included patient follow-up after the end of treatment, preventing conclusions about long-term benefits. Considering these substantial limitations, although the results are encouraging, future studies of higher methodological quality with longer treatment and follow-up periods are needed to definitively confirm the efficacy and safety of auricular acupuncture in the treatment of insomnia.