Will Your Drug Work?

Blood tests determine susceptibility to antidepressants

/ Author:  / Reviewed by: Joseph V. Madia, MD

(RxWiki News) With the massive differences in the human genome, prescribing medications can be tricky.  Fortunately, a new discovery may help doctors customize your medication by blood test.  

The Loyola University Medical Center reports on what could become the first accurate method of determining an antidepressant’s success. According to their study, this involves searching a blood sample for a protein called vascular endothelial growth factor (VEGF).

"Keep working with your doctor until you find the most effective depression medication."

Lead author on the study, Angelos Halaris M.D., Ph.D., of Loyola explains, “This would be the first time we would have a predictor for how well a patient would respond to an antidepressant.” With approximately sixty-percent of patients failing to respond to their first medication, this could mean faster relief for millions.

“It would greatly benefit our patients if we could predict ahead of time whether a given medication would be effective for a certain patient,” Dr. Halaris concures.

The study oversaw thirty-five patients taking Lexapro for major depressive disorder. Patients with higher levels of VEGF in their blood reacted better to Lexapro (escitalopram) and eighty-five percent of patients were relieved of at least some symptoms of depression, if not all. Conversely, less than ten percent of patients with low VEGF levels saw any relief.

Unfortunately, researchers do not understand why antidepressants work on some individuals and not others. Nonetheless, it appears higher levels of VEGF led to increased brain activity and regeneration of dormant nerve cells, reducing symptoms of depression. The converse was found true of lower levels. 

Findings support the neurogenesis theory ensuing that antidepressants "jumpstart" inactive brain cells and VEGF fuels the process.  The VEGF seems to instigate growth amongst blood circulation networks to keep the brain engaged and healthy.  

Doctors believe that this treatment will lead to pre-prescription blood test if further studies confirm results. 

Reviewed by: 
Review Date: 
December 16, 2011
Last Updated:
December 20, 2011