Response 7

· QUESTION: Discuss Restless Leg Syndrome and Periodic Limb Syndrome. Include etiology and neurobiological principles.

· Discuss treatments with an emphasis on pharmacologic treatments.

· Don't forget to include why and how these medications work to reduce symptoms by including the MOA, evidence for its use, and side effects along with patient education.

·

· Reply to at least one classmate (from a different discussion group)

· Posts are a minimum of 250 words, scholarly written, APA formatted (with some exceptions due to limitations in the D2L editor), and a minimum of 2 references (which may include the course textbook).

Response to Misty:

Restless leg syndrome (RLS) is a sleep-related sensorimotor disorder that is characterized by four cardinal symptoms, which include an overwhelming urge to move the legs, often with unpleasant sensations (achiness, tingling, internal feelings that “bugs” are inside your legs), symptoms provoked by rest or immobility, relief with movement, and worsening in the evening (Winkelman & Wipper, 2026). RLS is diagnosed clinically, as polysomnography is not required (Winkelman & Wipper, 2026). Risk factors include family history, northern European descent, female sex, and older age (greater than 65 years) (Winkelman & Wipper, 2026). Secondary causes of RLS are associated with iron deficiency anemia, end-stage kidney disease, multiple sclerosis, peripheral neuropathy, pregnancy, and Parkinson’s disease (Gabbard & M.d., 2014). Medications that can trigger or worsen RLS symptoms include selective serotonin reuptake inhibitors (SSRIs) and serotonin-norepinephrine reuptake inhibitors (SNRIs), dopamine antagonists, and centrally acting antihistamines (Winkelman & Wipper, 2026).

Periodic limb movements of sleep (PLMS) are involuntary, repetitive flexion movements of the lower extremities that are detected on polysomnography and occur at 15- to 30-second intervals during sleep (Kouri et al., 2023). PLMS are present in over 75% of patients with RLS and are considered the movement symptoms of RLS, but most individuals with PLMS do not have RLS (Kouri et al., 2023). Periodic limb movement disorder (PLMD) is a distinct diagnosis requiring the process of exclusion, which requires a PLMS index greater than 15 hours in the adult population, has clinically significant sleep disruption or daytime dysfunction not explained by an obvious disorder, and has the absence of RLS, untreated obstructive sleep apnea (OSA), REM sleep behavior disorder, or narcolepsy (Winkelman et al., 2025).

The pathophysiology of RLS and PLMD involves brain iron deficiency (BID), genetic predisposition, and dopaminergic dysfunction (Winkelman et al., 2025). BID is the key initial pathobiological factor, and several studies have consistently demonstrated low brain iron levels in patients with RLS (Winkelman & Wipper, 2026). BID leads to downstream hyperdopaminergic and hyperglutamatergic states that disrupt cortico-striatal-thalamic-cortical circuits (Xu et al., 2025). Approximately half of patients with RLS have a first-degree family member with RLS (Winkelman & Wipper, 2026). Researchers have found that people with RLS exhibit abnormal dopamine activity, particularly in brain and spinal cord regions that control movement and sensory signals (Winkelman & Wipper, 2026). The balance between D3 and D1 receptors is central to understanding both the therapeutic and augmenting effects of medications used to treat RLS (Ferré et al., 2026).

Iron supplementation is the guideline-recommended first-line treatment for all patients with serum ferritin levels below 100 ng/mL, as it replenishes brain iron stores (Winkelman & Wipper, 2026). Oral ferrous sulfate 325-650 mg daily or every other day showed similar efficacy to IV iron in patients with iron deficiency anemia who also had RLS, thus showing up to 75% improvement (Winkelman & Wipper, 2026). Side effects include constipation, diarrhea, nausea, and a metallic taste, with symptom relief taking one to three months (Winkelman & Wipper, 2026). First-line pharmacotherapy for RLS includes gabapentin, pregabalin, and gabapentin enacarbil, which act on voltage-gated calcium channels, thereby reducing calcium influx at presynaptic nerve terminals and decreasing the release of excitatory neurotransmitters such as glutamate (Winkelman et al., 2025). By inhibiting excitatory neurotransmitters, this drug class can reduce both sensory symptoms and hyperarousal states that disrupt sleep (Ferré et al., 2026). Through a systematic review of the management of RLS, gabapentin has shown over 70% improvement in symptoms related to this disorder over placebo (Winkelman & Wipper, 2026). Side effects include somnolence, dizziness, weight gain, cognitive dysfunction, depression, and suicidal ideation, as well as falls, which were of concern, particularly in the elderly population (Winkelman & Wipper, 2026). Educating patients on when to take this medication is important to stress, as it should be taken within one to two hours prior to symptom onset, as well as educating patients on the effects of sedation and to avoid driving until they know how the medication affects them, and continue to monitor their weight (Winkelman & Wipper, 2026).

Second-line pharmacotherapy includes dopamine agonists, which are FDA-approved to treat RLS, including pramipexole, ropinirole, and rotigotine (Winkelman et al., 2025). Dopamine receptor agonists, including D3 receptor agonists, activate inhibitory D2-like receptors and, at low doses, inhibit sensory signal transmission, thereby reducing the urge to move (Ferré et al., 2026). Side effects of dopamine agonists include somnolence, nausea, dizziness, nasal stuffiness, impulse control disorders, and worsening of RLS symptoms (Winkelman & Wipper, 2026). Patients must be questioned about impulse-control behaviors at each visit, and the possibility of worsening RLS symptoms, called augmentation, should be explained; for example, symptoms may occur earlier in the day and become more severe (Winkelman & Wipper, 2026). If augmentation occurs, do not increase the dose, as this will worsen the problem; instead, transitioning to gabapentin would be prudent (Winkelman & Wipper, 2026).

For PLMD without RLS, guidelines support the use of ropinirole to reduce periodic limb movements, and the American Academy of Sleep Medicine treats PLMD using the same methods as RLS (Winkelman et al., 2025). Overall, patients should be educated to avoid or minimize SSRIs/SNRIs, bupropion may be a safer alternative, dopamine antagonists, and diphenhydramine (Gabbard & M.d., 2014).

 

References

Ferré, S., García-Borreguero, D., & Earley, C. J. (2026). On the mechanisms of dopamine receptor agonists in restless legs syndrome.  Sleepj,  49(1), Article zsaf305.  https://doi.org/10.1093/sleep/zsaf305

Gabbard, G. O., & M.d. (2014).  Gabbard's treatments of psychiatric disorders, fifth edition (5th ed.). American Psychiatric Pub.

Kouri, I., Junna, M. R., & Lipford, M. C. (2023). Restless legs syndrome and periodic limb movements of sleep: From neurophysiology to clinical practice.  Journal of Clinical Neurophysiology,  40(3), 215–223.  https://doi.org/10.1097/wnp.0000000000000934

Winkelman, J. W., Berkowski, J. A., DelRosso, L. M., Koo, B. B., Scharf, M. T., Sharon, D., Zak, R. S., Kazmi, U., Falck-Ytter, Y., Shelgikar, A. V., Trotti, L. M., & Walters, A. S. (2025). Treatment of restless legs syndrome and periodic limb movement disorder: An American Academy of sleep medicine clinical practice guideline.  Journal of Clinical Sleep Medicine,  21(1), 137–152.  https://doi.org/10.5664/jcsm.11390

Winkelman, J. W., & Wipper, B. (2026). Restless legs syndrome: A review.  JAMA,  335(8), 703.  https://doi.org/10.1001/jama.2025.23247

Xu, Y., Guan, Y., & Lang, B. (2025). Unraveling restless legs syndrome: A comprehensive review of current research and future directions.  International Journal of General Medicine,  18, 4041–4055.  https://doi.org/10.2147/ijgm.s544680