The World Health Organization estimates that ADHD affects almost 39 million people worldwide. The disorder is characterized by a difficulty to control behavior and usually presents in children between the ages of 6 and 12. The neurodevelopmental disorder includes symptoms such as:
- Have difficulty focusing on one task
- Become bored with a an activity after a few minutes
- Are in attentive when taking instructions
- Individual Does not follow instructions
For a diagnosis to be made, symptoms must be present for 6 months and negatively affect two areas of the patient’s life (e.g., school and home).
ADHD is a common disorder and has a number of treatments. Commonly behavioral therapy is initially recommended but and increasing number of doctors are turning to medication. Methylphenidate, trade name Ritalin, is the first line drug but is associated with a number of side effects. These include:
- Dyskinesia (tics)
- Lethargy (drowsiness or fatigue)
- Appetite loss
- Hyperhydrosis (increased sweating)
- Blurred vision
- Dry eyes
As such, pharmacotherapy for ADHD can be cumbersome. Dosage is highly variable between patients and it can take months to find the right medication at the right dose. Almost 20% of individuals are non-responders to Ritalin, and alternative medication needs to be found in these patients.
The side effects of ADHD medication have been associated with polymorphisms in a number of genes. These include COMT DAT1, DRD2,DRD4, SNAP25, NET1, ADRA2A, and 5HTT. Individuals with polymorphisms in these genes may be at an increased risk of developing the common side effects of methylphenidate or being non responders to the drug.
Pharmacogenetics is able to help provide improved efficacy in ADHD pharmacotherapy. Genetic sequencing can identify individuals with known polymorphisms and clinicians and pharmacists can alter medication and dosage accordingly. This improves the speed with which the right medication is found at the right dose. MD Labs provides Rxight®, a genetic testing service that sequences over 18 genes for more than 60 known alleles. This allows clinicians to identify how patients will react to more than 200 common medications, including Ritalin. We currently offer genetic sequencing of ADRA2 and COMT, two genes associated with ADHD medication side effects.
Rxight® provides information about genetic variants for over 200 prescription medicines, including ADHD medicatioons. Testing is simple. DNA samples are extracted from a painless non-invasive cheek swab and sent to our labs for analysis. Patients receive a Personalized Medication Review® that is interpreted by a pharmacist certified in pharmacogenetics. Keeping the report on file allows pharmacists and clinicians to select medications that are compatible with a patient’s genetic characteristics.