The invention relates to agents that contain folic acid, vitamin B6 and vitamin B12, and to the use thereof in hyperhomocysteinemia for controlling homocysteine levels. The agents are mainly suitable for the preventive and acute treatment of vascular diseases, of pregnant women and neurodegenerative diseases and are particularly advantageous in cases where the homocysteine levels to be controlled are found in an individual suffering from renal failure or being treated with immune suppressors. The invention particularly relates to pharmaceutical agents and food supplements comprising a corresponding active ingredient combination and to agents in the form of commercial packages containing corresponding combination preparations or monopreparations for the combined use.