Mental health clinicians may need to check for iron deficiency and to prescribe an iron supplement if a deficiency is found.
1. Iron deficiency is well known to be a risk factor for restless legs syndrome.
Low iron stores may also be a risk factor for developing medication-induced akathisia.
So, if there is a history of restless legs syndrome or of medication-induced akathisia, the person’s iron status should be evaluated.
2. But serum iron is not the best test to order! Order a serum ferritin level. Ferritin is the best measure of the iron stores in the body.
3. The normal range for serum ferritin is above 24 ng/mL (24 mcg/L) for men and above 11 ng/mL (11 mcg/L) for women. However, in a patient with a history of restless legs syndrome, we should treat with an iron supplement if the serum ferritin is anything less than 50 ng/mL.
This cut-off has been shown to predict response to iron supplementation in persons with restless legs syndrome. The same cut-off may be appropriate for persons with a history of akathisia although this has not been specifically studied as of November 2016.