Asymmetric dimethylarginine (ADMA) is an endogenous methylated amino acid derived from arginine which can inhibit the activity of nitric oxide synthases. In various pathological states such as hypercholesterolemia, hyperglycemia, hyperhomocysteinemia, hypertension, coronary artery disease, heart failure, and stroke, plasma levels of ADMA may be increased and lead to inhibition of NO synthesis and endothelial dysfunction. Inhibition of ADMA synthesis or intensification of metabolism of this compound might indirectly lower ADMA. Antioxidants, estrogen, vitamin A, angiotensin converting enzyme inhibitors, angiotensin AT1 receptor antagonists, and also some hypolipemic, hypoglycemic and beta-adrenoreceptor blocking drugs decrease ADMA levels. In some situations like neurological disorders, decreased plasma levels of ADMA are noticed and drugs increasing the concentration of this compound could exert protective effects. It is reasonable to explore which drugs can increase or decrease ADMA levels and what their mechanism of that action is.