Restless legs syndrome (RLS) is a neurological disorder characterized by urges to move and uncomfortable sensations that occur primarily in the legs.1 RLS symptoms are relieved by movement. The symptoms follow a circadian pattern. Generally, symptoms are less pronounced during the day and worsen from evening to night time, leading to sleep disturbance in most patients.2,3 As the severity of the disease increases, symptoms may occur during the day as well, or the symptoms may affect parts of the body other than the legs.4 The global prevalence of RLS ranges from 7.2% to 11.2% and varies by race and country.3,5, 6, 7 In South Korea, 6.2%-8.7% of adults meet the diagnostic criteria for RLS, and 1.48% report moderate or severe symptoms.8 However, despite its relatively high prevalence and the significance of its clinical manifestations, RLS is often unrecognized or undiagnosed due to a lack of understanding of the disease,9 with only 6.2% of patients in a general-population study being diagnosed with RLS in primary care.5

The pathophysiological mechanisms of RLS are supported by hypotheses relating to iron deficiency and dopamine metabolism.10 Moreover, these two mechanisms seem to be related.11 Pharmacologic treatment of RLS includes iron agents, dopamine agonists, benzodiazepines, anticonvulsants, and opioids. Of these, dopamine agonists are the most commonly used.12,13 However, these medications only provide symptomatic relief, not a cure. Notably, when used for longer than several months, dopamine agonists can cause various adverse effects including augmentation and digestive symptoms, while anticonvulsants may lead to dizziness, drowsiness, and malaise.14 Therefore, the use of medication to treat RLS has limitations, especially when long-term treatment is indicated.

In East Asian countries, herbal medicines have been used for RLS and effectiveness has been previously demonstrated.15, 16, 17 Most of these studies included herbal medicines containing Paeoniae Radix.18 Paeoniae Radix is an herbal medicine that has been traditionally used for lower extremity discomfort, such as lower extremity cramps and pain. Consequently, it is most widely used to treat RLS clinically.19 While there have been various clinical studies using herbal medicines for RLS, there have been no clinical reports that explicitly focused on Paeoniae Radix to date.

In this case report, we described a female patient with diagnosed RLS and a 30-year history of headaches, who was successfully treated with herbal prescriptions containing Paeoniae Radix. Shortly after taking the herbal medicine, the patient's 2012 Revised International Restless Leg Syndrome Study Group Diagnostic Criteria (IRIS) score decreased significantly. Sleep disturbance resolved and the patient's headaches also completely disappeared. The patient remained in remission for 6 months. The patient's 30-year history of headaches and leg discomfort improved dramatically.