Methotrexate (MTX) is considered a mild immunosuppressing medication. It works by
decreasing the activity of certain types of white blood cells (WBCs). WBCs are also a part of
our body’s immune defense against infections, thus by definition MTX does suppress the
immune system to a mild degree. However, WBCs are overactive in autoimmune diseases
such as Juvenile Idiopathic Arthritis (JIA) and by suppressing their activity, MTX helps to
control the disease.

The term “immunomodulating” refers to a drug or substance that modifies the response of
the immune system in any way, which may include increasing or decreasing its function.