Restless legs syndrome with SSRI-associated worsening and low-normal ferritin (MEQ)

(i) Diagnosis and differentials. Chronic restless legs syndrome / Willis–Ekbom disease meeting IRLSSG essentials: urge to move with unpleasant sensations, rest worsening, movement relief, evening predominance, not solely a mimic. Partner kicks suggest coexistent PLMS but are not required for diagnosis. Differentials: nocturnal leg cramps, positional discomfort, neuropathy, anxiety restlessness, akathisia (less likely without antipsychotic), pure primary insomnia. SSRI increase temporally associated with worsening — medication-aggravated RLS.^[1][5][6]

(ii) Mechanisms. Brain-iron deficiency and dopaminergic diencephalospinal dysregulation with circadian evening peak explain the phenotype; normal haemoglobin does not exclude treatable low iron stores for RLS. Serotonergic antidepressants associate with increased PLMS and can unmask sensory symptoms — relevant to the escitalopram step-up.^[2][5][8]

(iii) Investigations and non-drug plan. Morning fasting iron panel already shows ferritin 62 ng/mL — within RLS repletion consideration band (commonly ≤75). Complete transferrin saturation, renal function, and pregnancy test if relevant. PSG not mandatory for typical clinical RLS. Non-drug: stop sedating antihistamines/alcohol, mental alerting at rest, sleep opportunity protection, planned zopiclone deprescribing once RLS controlled, IRLS baseline.^[2][7][8]

(iv) Pharmacologic steps. Iron repletion pathway (oral ferrous sulfate with vitamin C if appropriate; IV if oral fails/intolerant — sleep/medicine-guided). Prefer α2δ ligand (e.g. pregabalin titrated toward trial-supported ranges such as evening-weighted therapy up to ~300 mg/day as tolerated with renal/age caution) as first-line chronic drug to reduce augmentation risk; dopamine agonists second-line at lowest effective dose with ICD and augmentation counselling. Do not escalate dopamine agonists if earlier-day spread appears.^{[2][3][4][7][8]}

(v) Mood interactions. Continue treating MDD but review whether escitalopram can be adjusted, switched, or supported with non-SSRI options if mood allows (bupropion often discussed as relatively preferential for PLMS phenotypes — seizure risk and depression indication still govern). Treat RLS and depression together; residual sleep fragmentation maintains mood symptoms. Document suicide risk linked to sleepless nights; safety-net.^[5][6]