Causes of restless legs syndrome 

In many cases of restless legs syndrome (RLS) the exact cause is unknown.

When no cause can be found it is known as idiopathic, or primary restless legs syndrome. This can run in families and is most common in people younger than 40.


There is conflicting evidence about the role of a brain chemical called dopamine with restless legs syndrome.

Some people benefit from a type of medication called a dopamine agonist, which raises the levels of dopamine in the brain. This had led to some people arguing that the condition is related to problems with creating and breaking down dopamine in brain cells.

Dopamine levels naturally fall towards the end of the day, which may explain why the symptoms of restless legs syndrome are often worse in the evening and during the night.

Further research into this is needed. 

Underlying health condition

Secondary restless legs syndrome can occur as a complication of another health condition, or it can develop as a result of another health-related factor.

For example, you may develop secondary restless legs syndrome if you:


There are a number of triggers that do not cause restless legs syndrome, but can make symptoms worse. These include medications such as:

Other reported triggers include:

  • excessive smoking, caffeine or alcohol
  • being overweight or obese
  • stress
  • lack of exercise

Page last reviewed: 18/07/2013

Next review due: 18/07/2015