For a 60‑year‑old patient with several months of non‑restorative sleep, leg discomfort and urge to move the legs at night, and episodic involuntary leg movements during sleep, which medication—sertraline, melatonin, duloxetine, or gabapentin—is the most appropriate treatment?

Gabapentin is the Best Choice

Among the four options provided, gabapentin is the most appropriate medication for this patient with restless legs syndrome (RLS) and periodic limb movement disorder (PLMD).

Clinical Presentation Analysis

This 60-year-old patient presents with the classic tetrad of RLS:

• Urge to move the legs with discomfort
• Symptoms worse at night/evening
• Non-restorative sleep
• Involuntary leg movements during sleep (indicating concurrent PLMD)

Evidence-Based Recommendation

The 2025 American Academy of Sleep Medicine guidelines provide the strongest and most recent evidence for treatment selection 1:

Gabapentin receives a strong recommendation with moderate certainty of evidence for adults with RLS 1. This is one of only three medications to receive a "strong recommendation" designation (the others being pregabalin and IV ferric carboxymaltose).

Why Gabapentin Over the Other Options:

Sertraline (SSRI antidepressant):

• Not recommended and potentially harmful for RLS
• SSRIs are known to worsen or induce RLS symptoms
• No evidence supporting its use for RLS
• FDA labeling focuses on depression/anxiety disorders, not movement disorders 2

Melatonin:

• No guideline support for RLS treatment
• Not mentioned in the 2025 AASM guidelines as a treatment option
• Insufficient evidence for efficacy in RLS

Duloxetine (SNRI antidepressant):

• Not recommended and potentially harmful for RLS
• Like SSRIs, SNRIs can exacerbate RLS symptoms
• FDA labeling addresses anxiety and neuropathic pain, but not RLS 3
• No evidence supporting its use for RLS

Gabapentin:

• Strong recommendation from 2025 AASM guidelines 1
• Proven efficacy for both sensory symptoms (leg discomfort/urge to move) and motor symptoms (periodic limb movements)
• Improves sleep architecture and reduces PLMS index 4
• Mean effective dose approximately 1,855 mg daily, with therapeutic effects observed as early as week 4 4
• Does not carry the augmentation risk associated with dopaminergic agents

Treatment Algorithm

Step 1: Rule Out Iron Deficiency

Before initiating gabapentin, check ferritin levels. If ferritin <75 ng/mL, iron supplementation (oral or IV) should be first-line treatment, targeting ferritin >100 ng/mL 5, 6.

Step 2: Initiate Gabapentin if Iron Adequate

• Starting dose: 300 mg at bedtime
• Titration: Increase by 300 mg every 3-7 days based on response and tolerability
• Target dose range: 1,200-2,400 mg daily (divided doses or single evening dose)
• Timing: Administer 1-2 hours before symptom onset (typically evening)

Step 3: Monitor Response

• Assess symptom improvement at 4 weeks (therapeutic effects typically evident by this time 4)
• Evaluate sleep quality improvement
• Monitor for side effects (sedation, dizziness, peripheral edema)

Important Clinical Considerations

Common Pitfalls to Avoid:

• Do not use antidepressants (sertraline, duloxetine) as they can worsen RLS symptoms
• Do not start with dopamine agonists as first-line therapy due to augmentation risk (paradoxical worsening over time) 1, 5, 6
• Do not overlook iron deficiency—this is a treatable underlying cause

Advantages of Gabapentin:

• No augmentation phenomenon (unlike dopaminergic agents)
• Addresses both sensory and motor components of RLS/PLMD
• Improves sleep architecture beyond just reducing leg movements 4
• Particularly effective for patients with painful RLS symptoms 4

The shift away from dopamine agonists as first-line therapy represents a major paradigm change in RLS management, with α2δ ligands like gabapentin now preferred for long-term symptom control and quality of life improvement 5, 6.