What are the symptoms and treatment options for restless leg syndrome?

Symptoms of Restless Legs Syndrome

Restless legs syndrome is diagnosed by four essential clinical criteria: an urge to move the legs with uncomfortable sensations, worsening with rest/inactivity, relief with movement, and evening/nighttime predominance. 1, 2

Core Diagnostic Features

The American Academy of Sleep Medicine defines RLS by these mandatory criteria that must all be present 1, 2:

• Urge to move the legs - An irresistible compulsion to move, often (but not always) accompanied by uncomfortable or unpleasant sensations in the legs 1, 2
• Worsening with rest - Symptoms begin or worsen during periods of rest, inactivity, or immobility (such as sitting or lying down) 1, 2
• Relief with movement - Symptoms are partially or totally relieved by movement such as walking, stretching, or any leg activity, though symptoms return when movement stops 1
• Circadian pattern - Symptoms worsen or only occur in the evening or at night, typically after 6 PM 1, 2

How Patients Describe Their Symptoms

Patients use varied language to describe the uncomfortable sensations, but all must report an urge to move 3:

• Common descriptors include crawling, creeping, pulling, tingling, burning, itching, or aching sensations deep in the legs 3
• The sensations are typically bilateral but can be asymmetric 3
• Symptoms can occasionally affect the arms or other body parts, though legs are predominantly involved 2

Associated Clinical Features

Beyond the core criteria, patients commonly experience 2, 3:

• Periodic limb movements during sleep (PLMS) - Brief, recurrent leg movements occurring approximately every 15-30 seconds, present in most RLS patients but not required for diagnosis 2
• Sleep disturbance - Difficulty falling asleep or staying asleep due to the need to move, leading to significant sleep deprivation 3, 4
• Daytime consequences - Fatigue, mood disturbances, and impaired quality of life from chronic sleep disruption 4

Critical Distinctions from RLS Mimics

The American Academy of Sleep Medicine emphasizes distinguishing RLS from conditions that can appear similar 1:

• Nocturnal leg cramps - Painful, involuntary muscle contractions (typically calf) with no urge to move; relief comes from stretching the specific cramped muscle, not general movement 1
• Peripheral neuropathy - Numbness, tingling, or burning that is constant and positional rather than activity-dependent 1
• Positional discomfort - Relieved by position change rather than continued movement 5
• Akathisia - Inner restlessness from medications (especially antipsychotics) affecting the whole body, not just legs 5

Diagnostic Questions to Ask

To differentiate RLS from mimics, ask 1:

• "What does it feel like?" - RLS is an urge to move with dysesthesias, not pure pain or tightening 1
• "Is it relieved by movement?" - RLS improves with any movement and returns at rest; cramps improve with specific stretching 1
• "When is it worst?" - RLS has clear evening/nighttime worsening; neuropathy is typically constant 1

Severity Assessment

RLS severity ranges from mild to severe 4:

• Mild RLS - Occasional episodes with minimal sleep disruption 4
• Moderate-to-severe RLS - Frequent symptoms (≥15 episodes/month) significantly impacting sleep and daily function, typically requiring treatment 6
• The International RLS Rating Scale (IRLS) scores 0-40, with ≥15 indicating clinically significant disease requiring evaluation for treatment 6

Evaluation Requirements

The American Academy of Sleep Medicine recommends 5:

• Iron studies - Check serum ferritin and transferrin saturation in all patients, ideally morning fasting after avoiding iron supplements for 24 hours 5
• Medication review - Identify exacerbating medications including antihistamines, SSRIs, tricyclic antidepressants, lithium, and antipsychotics (dopamine antagonists) 5, 2
• Neurological examination - Assess for peripheral neuropathy signs 1
• Screen for secondary causes - Pregnancy, renal failure, and systemic iron deficiency are associated with high RLS rates 3

Note that RLS diagnosis is purely clinical based on history; there is no objective test, and polysomnography showing PLMS does not confirm or exclude the diagnosis. 2