Most secondary RLS cases have an onset after 40 years old. Secondary RLS are those associated with a variety of neurological disorders, iron deficiency, pregnancy, or chronic renal failure (Winkelman et al., 1996; Curgunlu et al., 2012; Srivanitchapoom et al., 2014). A study in Turkey revealed that severity of RLS symptoms is very closely related to low ferritin level (Curgunlu et al., 2012). In the earliest studies of RLS, some revealed that 25% of RLS patients have iron deficiency condition. The other correlated factors were diabetic peripheral neuropathy (Zobeiri and Shokoohi, 2014), painful neuropathies (Rutkove et al., 1996), ADHD (Roy et al., 2015), migraine (Zanigni et al., 2014), AS (Tekatas and Pamuk, 2015), leprosy (Padhi and Pradhan, 2014), inflammatory chronic demyelinating neuropathies like multiple sclerosis (Deriu et al., 2009) and Guillain–Barré syndrome (Marin et al., 2010), thyroid disease (Rodriguez Martin et al., 2015), poliomyelitis (Kumru et al., 2014), chronic venous disorder (McDonagh et al., 2007), autoimmune disease including Sjögren’s syndrome (Theander et al., 2010), rheumatoid arthritis (Hening and Caivano, 2008), inflammatory bowel disease (Becker et al., 2015), and Crohn’s disease (Hoek et al., 2015). Epidemiology studies also showed that the prevalence of RLS significantly increased in post-stroke patients, mainly in patients whose stroke topography lied on pyramidal tract and the basal ganglia-brainstem axis which were primarily involved in motor functions (Sechi and Sechi, 2013). Some certain drugs can cause or worsen RLS symptoms, such as psycotropics like antidepressants and neuroleptics, dopaminergic drugs, and some other drugs (Giudice, 2010) such as cumulative dopaminergic agonists effects in Parkinson’s disease patients (McDonagh et al., 2007). A study revealed that the strongest evidence for drug-induced RLS are for the following: escitalopram, fluoxetine, L-dopa/carbidopa and pergolide, L-thyroxine, mianserin, mirtazapine, olanzapine, and tramadol (Hoque and Chesson, 2010).