However, restless leg syndrome has been associated with pregnancy, obesity, smoking, iron deficiency
and anemia, nerve disease, polyneuropathy (which can be associated with hypothyroidism, heavy metal toxicity, toxins, and many other conditions), other hormone disease, such as diabetes, and kidney failure.
Some drugs and medications have been associated with restless leg syndrome including caffeine, alcohol, H2-histamine blockers and certain antidepressants.