• Personalized medicine improves the patients' treatment, Look at ADHD
  • SEYED MAHDI EMAMI MEYBODI,1,* AMIN JAVADIFAR,2
    1. Student Research Committee, Afzalipour School of Medicine, Kerman University of Medical Sciences, Kerman, Iran
    2. Student Research Committee, School of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran


  • Introduction: Methylphenidate (MPH) reduces hyperactive-impulsive symptoms common in children with attention-deficit/hyperactivity disorder. however, response and tolerability varies widely. We hypothesized gene variants may moderate MPH effects in children ADHD.
  • Methods: The onset of personalized medicine goes back to Avicenna when he points out that the diseases caused by the imbalance of the main body fluids. Now, personalized medicine actually means "right treatment for right person at right dose and right time". Today, due to different responses of patients to drugs, studies in personalized medicine has been developed and are in progress. The most important factors responsible for different responses to treatment are genetic variations. Pharmacogenomics deals with the influence of acquired or inherited genetic variations on pharmacokinetics and pharmacodynamics of drugs. Neuroleptics and psychotropic need to be personalized because of their side effects. Pharmacogenetic tests has the potential to improve clinical outcomes through increased efficacy and reduced toxicity and side effects. ADHD is the most commonly detected mental disorder of children. Children with ADHD may be hyperactive and unable control their instincts. Or they may have trouble paying attention. the underlying pathomechanism of ADHD are not fully understood. The first line treatment of hyperactivity symptom is methylphenidate but the response of the patients is widely variable. MPH works by preventing the reuptake of dopamine (DA) and norepinephrine (NE) through inhibition of the DA (SLC6A3) and NE transporters (SLC6A2), resulting in an increase in extracellular DA and NE. ¬the studies showed that genetic variants that is related to Neurotransmitter synthesis and degradation، Neurotransmitter reuptake، Neurotransmitter receptor binding، Neurotransmitter release، Neuronal/synaptic plasticity and synaptic effectors and Downstream neurotransmitter effects affect on the response to the methylphenidate. So far, numerous attainments have been done in this field, but there are contradictory results on the impact or ineffectiveness of such variations in responses to the treatment. Despite many efforts on finding effective factors related to methylphenidate treatment, patients still suffering from drug side effects. Therefore, further studies in this field needed to determine effective biomarkers to improve ADHD patients' treatment.
  • Results: Some gene variants demonstrate different response to the MPH.
  • Conclusion: Our knowledge about the gene variants that affect on methylphenidate response help us to manage the symptom of ADHD better as compared to before.
  • Keywords: ADHD-Methylphenidate-genetic variants