Opioids, other drugs, and drugs that worsen RLS

Synthesis of the evidence on (a) opioids (oxycodone-naloxone, methadone, buprenorphine, tramadol) as a treatment/bridge option for treatment-refractory or dopamine-agonist-augmented RLS, (b) other non-dopaminergic, non-alpha-2-delta drugs (clonazepam, perampanel, dipyridamole, cannabinoids), and (c) drugs that aggravate or precipitate RLS (SSRIs/SNRIs, mirtazapine, antipsychotics, metoclopramide, lithium, and related agents). All claims below cite a study note filename (in knowledge-base/studies/) or a PMID. Medical disclaimer: nothing here is individual medical advice; opioid therapy for RLS carries real dependence/misuse risk and must be initiated, adjusted, and tapered only under physician supervision; never start, stop, or substitute any RLS medication without medical guidance.

What is established (grade A/B)

• Prolonged-release (PR) oxycodone-naloxone is efficacious for severe, dopaminergic-refractory RLS: in a 306-patient multicentre RCT, IRLS sum score fell by -16.5 (SD 11.3) on oxycodone-naloxone versus -9.4 (SD 10.9) on placebo at 12 weeks (between-group difference 8.15 points, 95% CI 5.46-10.85, p<0.0001), with benefit sustained through a 40-week open-label extension (mean sum score 9.7 at the end) (2013-trenkwalder-oxycodone-naloxone-rct.md).
• Low-dose opioids (predominantly methadone and oxycodone) provide durable, largely stable long-term control of augmented RLS: in the National RLS Opioid Registry (n=500), median dose was 30.0 morphine milligram equivalents (MME) at baseline and rose to a median of only 37.5 MME by 5 years, with RLS severity essentially unchanged (13.3 to 13.1 on the IRLS scale) and most participants (66.1%) showing little or no dose change over 5 years (2021-winkelman-opioid-registry-baseline.md, 2026-winkelman-opioid-registry-5year.md; consistent with the earlier 2-year, n=448 cohort showing a median 0 MME change, 2023-winkelman-national-rls-opioid-registry.md).
• RLS-like restlessness during opioid withdrawal is a real, quantifiable, drug-specific phenomenon, not just anecdote: in a controlled comparison, 50.8% of patients detoxifying from opioids met criteria for RLS versus 21.7% of patients detoxifying from alcohol (n=304 total; chi-square=27.96, p<0.001; adjusted OR 2.05, 95% CI 1.09-3.88) (2016-mackie-detox-alcohol-opioid-rls-prevalence.md).
• Antidepressant-induced/aggravated RLS is real but highly drug-specific, not a class effect, confirmed by two independent, systematically-searched reviews A: mirtazapine and several non-SRI agents (escitalopram, fluoxetine, olanzapine, tramadol among others) carry the strongest evidence for causing or worsening RLS, while bupropion may reduce RLS symptoms, at least short-term (2017-kolla-antidepressants-rls-systematic-review.md; 2010-hoque-chesson-pharmacologically-induced-rls-review.md). A prospective four-site cohort quantified this at the drug level: 9% of patients starting a modern antidepressant developed/worsened RLS, driven overwhelmingly by mirtazapine (28% of mirtazapine starts) versus 0% on reboxetine (2008-rottach-second-generation-antidepressants-rls.md). A large multinational inpatient pharmacovigilance program (340,099 monitored patients) found that over 80% of all psychotropic-drug-induced RLS cases were attributable to just two drugs -- mirtazapine and the antipsychotic quetiapine -- both with antihistaminergic activity at low dose (2026-fugger-secondary-rls-pharmacovigilance.md).
• Clonazepam has RCT-level support (albeit from a very small, historic trial) for improving RLS-related sleep disruption and dysesthesia versus placebo (1984-montagna-clonazepam-vibration-rct.md), and dipyridamole -- a non-opioid, non-dopaminergic adenosine-pathway drug -- is confirmed effective for RLS sensory/motor symptoms and objective sleep/arousal measures in a placebo-controlled crossover RCT (2021-garcia-borreguero-dipyridamole-rct.md), giving this project two RCT-backed, non-dopamine-agonist drug options beyond opioids.
• Prior long-term dopamine-agonist exposure blunts response to subsequent non-dopaminergic drugs even in patients who never met formal augmentation criteria: a post hoc analysis of two crossover RCTs (dipyridamole n=28, suvorexant n=40) found significantly worse responses in dopamine-agonist-experienced versus dopamine-agonist-naive patients across IRLS, CGI-Severity, and PLM measures (2025-garcia-borreguero-subclinical-augmentation-posthoc.md) -- an important caveat when planning any drug-switching strategy.

Emerging C

• Methadone's use in refractory RLS rests on foundational but uncontrolled evidence: in the original case series, 17 of 27 evaluable patients stayed on methadone (mean 15.5 mg/day) for a mean of 23 months with at least 75% symptom reduction and no augmentation, though 2 dialysis-dependent patients died while on treatment (cause not adjudicated) and 8 discontinued (2005-ondo-methadone-refractory-case-series.md).
• Buprenorphine does not appear to reliably suppress RLS the way full mu-agonists do: 13.2% of patients on long-term buprenorphine/naloxone maintenance for opioid use disorder had definite/probable current RLS symptoms (moderate severity, sleep-disrupting), and most were on no RLS-directed medication at all (2023-wipper-buprenorphine-oud-rls-prevalence.md).
• Opioid withdrawal produces a transient RLS-like state responsive to pregabalin: in 19 patients undergoing buprenorphine-assisted opioid detoxification, 10 developed RLS symptoms (onset after a mean 1.7 days of abstinence), and pregabalin improved both symptoms and sleep quality (2017-gupta-opioid-withdrawal-rls-pregabalin.md).
• Perampanel (a selective AMPA-receptor antagonist) showed large open-label improvement in RLS severity (IRLS 23.7 to 11.5) and periodic leg movements (index 27.8 to 4.36) in 20 treatment-naive patients, but only as uncontrolled Class IV evidence (2017-garcia-borreguero-perampanel-open-trial.md).
• Metoclopramide (a dopamine D2-receptor antagonist antiemetic) is an emerging, case-level-and-cohort confirmed RLS aggravator: RLS occurred in 75% of systemic sclerosis patients taking metoclopramide versus 26.3% of those not taking it (p=0.02; 2013-ostojic-metoclopramide-systemic-sclerosis-rls.md), and case reports document acute, reversible RLS after both oral and intravenous metoclopramide (2024-aljunaid-oral-metoclopramide-rls-case.md).
• Lithium is an emerging but uncommon cause of RLS among its broader family of movement-disorder side effects: a systematic multi-database literature review spanning 1949-2021 identified 10 clearly labeled RLS cases (plus 7 more in a less well-defined subgroup) among 1,100 individuals with lithium-associated movement disorders (2022-rissardo-lithium-movement-disorder-review.md).
• A single detailed case report illustrates the practical "switch to bupropion" strategy: citalopram 60mg/day-induced RLS resolved completely within 3 weeks of switching to bupropion plus sertraline, with no recurrence at 6 months (2007-perroud-citalopram-induced-rls-bupropion.md).
• The endogenous-opioid-deficiency hypothesis has direct human tissue support: postmortem RLS thalamus shows significantly reduced beta-endorphin- and Met-enkephalin-positive cells versus controls, with normal substantia nigra tyrosine hydroxylase (arguing for an opioid-specific, not purely dopaminergic, deficit) (2009-walters-postmortem-opioid-thalamus.md).
• Practical, expert-consensus guidance exists for using opioids safely in refractory RLS (lower doses than chronic-pain use; oxycodone or methadone preferred; opioid contracts, urine screens, and prescription monitoring recommended), though this is Grade D expert opinion rather than new trial evidence (2018-silber-opioid-appropriate-use-consensus.md), echoed by IRLSSG/AAN/AASM guidelines that reserve opioids for the most severe, treatment-resistant augmentation cases (2016-garcia-borreguero-augmentation-prevention-treatment-guidelines.md, 2016-winkelman-aan-treatment-guideline.md, 2025-winkelman-aasm-guideline-rls.md).

Contested or negative findings

• Cannabidiol (CBD) showed no benefit over placebo for RLS/WED severity in an exploratory analysis of a phase II/III RCT in Parkinson's disease patients with REM sleep behavior disorder (6 CBD vs 12 placebo) (2022-de-almeida-cbd-rls-pd-rbd-negative-rct.md) -- directly at odds with the more optimistic but far lower-quality cannabinoid literature (a 2026 scoping review found only 7 eligible studies, all case reports/surveys/post hoc analyses, and explicitly concluded evidence is "insufficient to support clinical recommendations," 2026-cannabinoids-rls-scoping-review.md).
• SSRIs specifically may not carry the class-wide RLS risk commonly assumed: a WHO VigiBase disproportionality analysis of over 14 million pharmacovigilance reports found serotonin reuptake inhibitors (SRIs) were the only antidepressant class not significantly associated with RLS when compared against other antidepressant classes, even though antidepressants overall were linked to RLS (2020-revet-antidepressants-movement-disorders-vigibase.md) -- a genuine tension with the case-report- heavy literature implicating individual SSRIs (escitalopram, citalopram, fluoxetine) in the Hoque & Chesson and Kolla systematic reviews and the Rottach cohort above.
• An acute pharmacological "challenge" study found that neither naloxone (opioid antagonist) nor metoclopramide (dopamine antagonist) provoked RLS sensory or motor symptoms in drug-naive patients (2001-winkelmann-opioid-dopamine-antagonist-challenge.md) -- an apparent paradox alongside the clear chronic aggravating effect of metoclopramide seen in cohort and case data above, suggesting RLS vulnerability to dopamine/opioid blockade may depend on chronic exposure, prior sensitization, or baseline brain iron status rather than acute receptor occupancy alone.
• Beta-blockers, named as a possible aggravator in this project's search hints, are not well supported as such by the literature actually available: identifiable reports are old (1980s), low-detail case-report letters, and at least two describe propranolol being used to treat (not cause) SSRI- or imipramine-withdrawal-induced akathisia/restlessness (PMID 24568368, PMID 3717447) -- these were too thin on reportable detail to write full study notes without inventing content (per this project's honesty rules), but the "beta-blockers worsen RLS" hypothesis should be treated as unconfirmed and possibly backwards pending better data.
• Diphenhydramine and other classic first-generation antihistamines are widely assumed (including in this project's own anchor facts and in existing guideline-review notes such as 2026-winkelman-rls-jama-clinical-review.md) to aggravate RLS, plausibly via the same antihistaminergic mechanism implicated in mirtazapine/quetiapine (2026-fugger-secondary-rls-pharmacovigilance.md), but no dedicated controlled or cohort study specifically on diphenhydramine and RLS could be confirmed via PubMed search for this sweep -- this remains a plausible but currently unconfirmed extrapolation, not established evidence.
• Desipramine is sometimes suggested clinically as a "safer" tricyclic antidepressant for RLS patients (by analogy to bupropion's low-serotonergic profile), but no dedicated RLS study on desipramine could be found in this search sweep; this recommendation should currently be treated as unverified extrapolation.

Mechanistic picture in 5 bullet points

1. Endogenous mu-opioid-receptor (MOR) signalling appears deficient in RLS: postmortem RLS thalamus shows reduced beta-endorphin/Met-enkephalin (2009-walters-postmortem-opioid-thalamus.md), and mice lacking MOR alone or all three classical opioid receptors reproduce RLS-like circadian hyperactivity, anemia, and abnormal iron handling (2020-lyu-mu-opioid-receptor-knockout-mouse.md, 2019-lyu-triple-opioid-receptor-knockout-mouse.md; synthesized in 2024-walters-opioid-melanocortin-review.md).
2. A striatal striosome-to-entopeduncular (GPi-equivalent) pathway that co-expresses mu-opioid and D1 dopamine receptors becomes hypersensitized under experimental brain iron deficiency, and the mu-agonist methadone suppresses this abnormal circuit response -- a proposed physical convergence point between the iron, dopamine, and opioid hypotheses of RLS (2026-valle-leon-striatal-entopeduncular-opioid-dopamine-model.md).
3. Despite this chronic-deficiency model, acutely blocking opioid or dopamine receptors in drug-naive patients does not itself provoke RLS symptoms (2001-winkelmann-opioid-dopamine-antagonist-challenge.md), implying the dysfunction is circuit-specific and likely dependent on chronic exposure or an underlying sensitized (e.g., iron-deficient) state rather than a simple acute receptor-occupancy deficit.
4. RLS, antipsychotic-induced akathisia, and opioid-withdrawal restlessness may share overlapping striatal MOR-pathway mechanisms, which would explain both why dopamine-blocking antipsychotics can precipitate RLS/akathisia-like states and why opioid withdrawal itself reliably produces a transient RLS phenocopy (2024-ferre-akathisia-opioid-withdrawal-mechanisms.md, supported by 2016-mackie-detox-alcohol-opioid-rls-prevalence.md and 2017-gupta-opioid-withdrawal-rls-pregabalin.md).
5. Drugs that aggravate RLS cluster mechanistically: dopamine-D2-receptor antagonists (metoclopramide, antipsychotics such as quetiapine and olanzapine), and antidepressants with combined serotonergic/noradrenergic/antihistaminergic activity (especially mirtazapine). The convergence of mirtazapine and quetiapine as the top two triggers in the largest real-world dataset points to histamine-receptor antagonism as a candidate shared mechanism (2026-fugger-secondary-rls-pharmacovigilance.md) -- distinct from, but potentially additive to, the adenosine-hyperarousal and iron-dopamine mechanisms documented in this knowledge base's other topic files.

Implications for a non-drug long-term plan for people currently on dopamine agonists or alpha-2-delta ligands

• If augmentation forces a taper off a dopamine agonist, the best-evidenced pharmacological bridge is a low-dose opioid (oxycodone or methadone), per expert consensus (2018-silber-opioid-appropriate-use-consensus.md) and confirmed effective and durable by RCT and registry data (2013-trenkwalder-oxycodone-naloxone-rct.md, 2021-winkelman-opioid-registry-baseline.md, 2026-winkelman-opioid-registry-5year.md) -- but this is still a drug with its own dependence considerations, and initiation/titration must be physician-supervised, never self-directed. Expect a largely stable long-term dose (median ~30-38 MME) for most patients.
• Anticipate a second, later withdrawal-related flare when eventually tapering the opioid bridge itself, not only during the dopamine-agonist taper: roughly half of patients withdrawing from opioids show RLS-like restlessness (2016-mackie-detox-alcohol-opioid-rls-prevalence.md, 2017-gupta-opioid-withdrawal-rls-pregabalin.md), which the alpha-2-delta ligand already likely in the regimen (pregabalin/gabapentin) can help manage.
• Perform active medication reconciliation to remove RLS-aggravating drugs prescribed for unrelated reasons: mirtazapine and quetiapine together account for the large majority of drug-induced RLS in the best available real-world dataset (2026-fugger-secondary-rls-pharmacovigilance.md); metoclopramide (an antiemetic) is a clear, quantifiable aggravator (2013-ostojic-metoclopramide-systemic-sclerosis-rls.md, 2024-aljunaid-oral-metoclopramide-rls-case.md) and should be avoided or substituted when possible.
• If an antidepressant is medically necessary, bupropion has the most consistent evidence of being RLS-neutral-to-beneficial (2017-kolla-antidepressants-rls-systematic-review.md, 2010-hoque-chesson-pharmacologically-induced-rls-review.md, 2007-perroud-citalopram-induced-rls-bupropion.md); avoid mirtazapine specifically. Do not assume all SSRIs are equally risky -- the largest pharmacovigilance dataset found no significant class-level signal for SRIs versus other antidepressants (2020-revet-antidepressants-movement-disorders-vigibase.md), so an individualized, drug-by-drug review is more evidence-consistent than blanket avoidance.
• Consider non-opioid, non-dopaminergic adjuncts with at least small-RCT support for residual symptoms: clonazepam for sleep/dysesthesia (1984-montagna-clonazepam-vibration-rct.md) and dipyridamole for adenosine-pathway symptoms (2021-garcia-borreguero-dipyridamole-rct.md), on top of the iron-repletion and alpha-2-delta-ligand foundation documented elsewhere in this knowledge base.
• Do not present cannabis/CBD as an evidence-based option yet: the only placebo-controlled RCT identified was negative (2022-de-almeida-cbd-rls-pd-rbd-negative-rct.md), and the rest of the literature is scoping-review-level at best (2026-cannabinoids-rls-scoping-review.md).
• Set realistic, honest expectations about any opioid-bridge component: even in the most favorable long-term registry data, roughly a quarter to a third of patients require dose increases over years (2026-winkelman-opioid-registry-5year.md), and even buprenorphine (a lower-abuse-liability option) does not reliably prevent breakthrough RLS (2023-wipper-buprenorphine-oud-rls-prevalence.md). Opioids are best framed as a supervised bridge/rescue option nested inside the broader iron-repletion and alpha-2-delta-ligand-based plan -- never as a "cure" or a substitute for addressing brain iron status.

Open questions

• Whether the mirtazapine/quetiapine antihistaminergic mechanism (2026-fugger-secondary-rls-pharmacovigilance.md) generalizes to classic OTC antihistamines like diphenhydramine has not been directly tested by any controlled or cohort study identified in this sweep -- a notable gap given how commonly diphenhydramine is used as an OTC sleep aid.
• The true long-term (beyond 5 years) abuse-liability, tolerance, and opioid-use-disorder risk of low-dose opioid therapy for RLS remains unclear from purely observational, survivorship-enriched registry data (2021-winkelman-opioid-registry-baseline.md, 2026-winkelman-opioid-registry-5year.md).
• Whether perampanel or other AMPA/glutamatergic drugs remain effective specifically in dopamine-agonist- augmented (rather than treatment-naive) patients has not been tested (2017-garcia-borreguero-perampanel-open-trial.md), an important gap given that prior dopamine-agonist exposure blunts response to other non-dopaminergic drugs (2025-garcia-borreguero-subclinical-augmentation-posthoc.md).
• The clinical relevance of beta-blockers to RLS risk is unresolved given sparse, old, and possibly direction-reversed evidence (see Contested section); a modern, adequately powered study is lacking.
• Why acute opioid/dopamine-receptor blockade fails to provoke RLS in drug-naive patients (2001-winkelmann-opioid-dopamine-antagonist-challenge.md) while chronic opioid withdrawal reliably does (2016-mackie-detox-alcohol-opioid-rls-prevalence.md) is mechanistically unresolved -- relevant to this project's brain-simulation component.
• No confirmed primary study on desipramine-and-RLS was located in this sweep; its "safer alternative" status is currently extrapolation, not evidence.

Notes in this topic

New notes written for this sweep:

• 2013-trenkwalder-oxycodone-naloxone-rct.md -- Landmark 306-patient RCT: PR oxycodone-naloxone significantly reduced severe, dopaminergic-refractory RLS symptoms versus placebo B.
• 2005-ondo-methadone-refractory-case-series.md -- Original case series: low-dose methadone controlled RLS long-term in dopaminergic-refractory patients without augmentation C.
• 2018-silber-opioid-appropriate-use-consensus.md -- IRLSSG expert-consensus practical guide to safe, low-dose opioid use in refractory RLS D.
• 2021-winkelman-opioid-registry-baseline.md -- National RLS Opioid Registry baseline/1-year data (n=500): low-dose opioids, mostly stable dosing B.
• 2026-winkelman-opioid-registry-5year.md -- Same registry at 5 years (n=410): doses and RLS severity remain largely stable long-term B.
• 2023-wipper-buprenorphine-oud-rls-prevalence.md -- RLS symptoms surprisingly common (13.2%) in buprenorphine/naloxone-maintained opioid-use-disorder patients C.
• 2017-gupta-opioid-withdrawal-rls-pregabalin.md -- Half of opioid-detox patients (n=19) developed transient RLS relieved by pregabalin C.
• 2016-mackie-detox-alcohol-opioid-rls-prevalence.md -- RLS twice as common during opioid- versus alcohol-detoxification (50.8% vs 21.7%, n=304) B.
• 2024-ferre-akathisia-opioid-withdrawal-mechanisms.md -- Hypothesis paper linking RLS, antipsychotic akathisia, and opioid-withdrawal restlessness via shared striatal MOR-neuron mechanisms D.
• 1984-montagna-clonazepam-vibration-rct.md -- Earliest controlled RLS trial (n=6): clonazepam improved sleep quality and dysesthesia versus placebo B.
• 2017-garcia-borreguero-perampanel-open-trial.md -- Open trial (n=22): AMPA-antagonist perampanel markedly improved RLS symptoms and periodic leg movements C.
• 2026-cannabinoids-rls-scoping-review.md -- Scoping review: only 7 low-quality studies on cannabinoids for RLS identified; evidence judged insufficient for recommendations D.
• 2022-de-almeida-cbd-rls-pd-rbd-negative-rct.md -- Small RCT (n=18): cannabidiol showed no benefit over placebo for RLS/WED in Parkinson's disease with REM sleep behavior disorder (Grade B, negative).
• 2008-rottach-second-generation-antidepressants-rls.md -- Prospective cohort: 9% of new antidepressant starts caused/worsened RLS; mirtazapine worst (28%), reboxetine 0% B.
• 2017-kolla-antidepressants-rls-systematic-review.md -- Systematic review of 18 studies: mirtazapine and venlafaxine worsen RLS/PLM, bupropion may help A.
• 2010-hoque-chesson-pharmacologically-induced-rls-review.md -- Quality-scored literature review: strongest RLS-inducing evidence for escitalopram, mirtazapine, olanzapine, tramadol, and others A.
• 2026-fugger-secondary-rls-pharmacovigilance.md -- Large multinational pharmacovigilance program (n=340,099): over 80% of drug-induced RLS traced to mirtazapine and quetiapine B.
• 2020-revet-antidepressants-movement-disorders-vigibase.md -- WHO VigiBase analysis: antidepressants overall linked to RLS, but SRIs specifically not significantly associated versus other classes C.
• 2007-perroud-citalopram-induced-rls-bupropion.md -- Case report: citalopram-induced RLS resolved after switching to bupropion plus sertraline C.
• 2013-ostojic-metoclopramide-systemic-sclerosis-rls.md -- Case-control: RLS in 75% of systemic sclerosis patients on metoclopramide versus 26% not on it C.
• 2024-aljunaid-oral-metoclopramide-rls-case.md -- Case report: oral metoclopramide triggered acute, reversible RLS C.
• 2001-winkelmann-opioid-dopamine-antagonist-challenge.md -- Acute naloxone/metoclopramide challenge did NOT provoke RLS symptoms in drug-naive patients (Grade C, negative).
• 2022-rissardo-lithium-movement-disorder-review.md -- Literature review (1,100 cases): lithium associated with RLS among other movement disorders C.

Pre-existing notes found and referenced (written for other topic sweeps, relevant here):

• 2009-walters-postmortem-opioid-thalamus.md -- Postmortem RLS thalamus shows reduced beta-endorphin and Met-enkephalin, supporting an endogenous-opioid-deficiency hypothesis C.
• 2013-garcia-borreguero-irlssg-long-term-guidelines.md -- IRLSSG long-term guideline grading pregabalin and dopamine agonists' multi-year efficacy D.
• 2015-trenkwalder-rls-therapies-augmentation-review.md -- Review noting scant controlled data once first-line treatment fails or augmentation occurs D.
• 2016-de-biase-oxycodone-naloxone-intractable-rls.md -- Review of PR oxycodone-naloxone use in intractable, augmented RLS D.
• 2016-garcia-borreguero-augmentation-prevention-treatment-guidelines.md -- Consensus guideline: opioids reserved for the most severe, treatment-resistant augmentation cases D.
• 2016-winkelman-aan-treatment-guideline.md -- AAN guideline grading dopaminergic/alpha-2-delta drugs; augmentation risk flagged D.
• 2018-garcia-borreguero-open-label-dipyridamole.md -- Open-label pilot: dipyridamole improved RLS symptoms and sleep, first test of the adenosine hypothesis C.
• 2018-wang-acute-drug-withdrawal-rls-symptoms.md -- PSG/EMG study of acute withdrawal from pramipexole, gabapentin, and oxycodone C.
• 2019-lyu-triple-opioid-receptor-knockout-mouse.md -- Triple opioid-receptor knockout mice show RLS-like hyperactivity plus iron/anemia abnormalities E.
• 2020-lyu-mu-opioid-receptor-knockout-mouse.md -- Mu-opioid-receptor knockout mice replicate RLS-like anemia, iron handling, and circadian motor phenotype E.
• 2021-garcia-borreguero-dipyridamole-rct.md -- Placebo-controlled crossover RCT confirms dipyridamole benefit, supporting adenosine signalling in RLS B.
• 2023-winkelman-national-rls-opioid-registry.md -- 2-year registry (n=448): stable opioid dosing, no average worsening of RLS severity C.
• 2024-walters-opioid-melanocortin-review.md -- Review synthesizing the endogenous-opioid-deficiency and POMC/melanocortin hypotheses of RLS D.
• 2025-garcia-borreguero-subclinical-augmentation-posthoc.md -- Post hoc RCT analysis: prior dopamine- agonist exposure blunts response to non-dopaminergic drugs (dipyridamole, suvorexant) B.
• 2025-winkelman-aasm-guideline-rls.md -- AASM 2025 guideline: iron/gabapentinoid-first approach, against standard dopamine-agonist use D.
• 2026-valle-leon-striatal-entopeduncular-opioid-dopamine-model.md -- Rodent model: brain iron deficiency sensitizes the striatal MOR/D1 pathway; methadone suppresses the abnormal response E.
• 2026-winkelman-rls-jama-clinical-review.md -- 2026 JAMA review reconfirming augmentation rates and the first-line shift to gabapentinoids and iron D.