Intuniv : ADHD Non-Stimulant Medication
Intuniv is a newer medication for the treatment of ADHD in children and teens that gained its approval from the FDA and was available to pharmacies in November, 2009.
Intuniv is not a stimulant medication, and may be helpful to the estimated 25-30% of children with ADHD who do not benefit from stimulant medications. Instead, Intuniv is a form of Guanfacine (Tenex) which has been used for years as a blood pressure medication in adults, and has also been used as an adjunct medication in the treatment of ADHD individuals with temper or anger problems, or oppositional defiant disorder. Now in the form of Intuniv, this medication seems to have a wider range of symptoms that benefit from its use than just anger or oppositional behavior.
It appears that Intuniv (guanfacine) works in the pre-frontal cortex to help the brain to increase the available supply of glutamate, an excitatory neurotransmitter. About one-third of all neurotransmitters in the brain are glutamate, and working together with dopamine and norepinephrine, glutamate helps to improve the functioning of the pre-frontal cortex - improving focus and attention, decreasing impulsive anger and frustration.
Families will find Intuniv easier to manage then Tenex, as it is a once-a-day medication, where Tenex was twice-a-day dosing. Also, Intuniv is not a stimulant, so it will be easier for doctors to prescribe the medication, and easier for families to pick up a refill at the pharmacy. Also, Intuniv has no known potential for abuse or dependence, so it may be helpful for those with both ADHD and a co-morbid history of addiction.
Early reports on Intuniv indicate that the effects and benefits of the medication are not just one day, but actually have benefit for the next morning with the child or teen wakes up, and many families know that the early morning can be one of the most difficult times of the entire day.
While Intuniv can be used along with stimulant medications, for many children and teens it is proving to be good enough all by itself. One doctor reports that he has seen positive results in his patients with "inattentive ADHD" helping them to focus better and longer. Others report that Intuniv may also help with those difficult, angry, ODD, and perhaps early on-set bipolar disordered kids and teens. And for those kids, Intuniv should be much safer than the antipsychotics that are often prescribed.
There is a lot that remains to be seen and reported. I'm not sure that I'd want my child to get in too early on this medication and take some time to see how others do with it, let it get a bit of a track record. In the studies that Shire had done for FDA approval, there were some significant side-effects reported, and something like 80% of the people who began the study dropped out over the course of the study - though the study was something like two years long so that might be why...
But for many families it will be worth watching, listening, and asking questions of their physicians. It should be a good discussion at your local CHADD meetings.
As always, we would like to see people trying Attend and Extress first, but there certainly are situations where the alternatives simply are not going to be effective enough and a medication like this will have to be used.
It is strongly recommended by some physicians that Intuniv not be used with certain other drugs, especially Prozac, Paxil, Luvox, Trileptal (or Tegretol), Provigil, and others in these classes.
We don't consider ourselves experts on Intuniv, but here are some websites with more information from people who are:
Here is a video clipped from YouTube discussing the targeted nature of Intuniv in the treatment of ADHD :
What is the Relationship Between Dopamine, Norepinephrine, and Glutamate? And How are They Related to ADHD?
One-third of the neurotransmitters in the brain are glutamate, and brain research is now looking at the intricate relationships between glutamate, dopamine, and nor-epinepherine in the functioning of the pre-frontal cortex. Research is revealing that the glutamate network neurotransmissions from the pre-frontal cortex to other areas of the brain are enhanced by dopamine and nor-epinepherine. Too little dopamine or nor-epinepherine is a problem, and too much is a problem. And the importance of glutamate in PFC functioning is beginning to come to the forefront in research.
Neuro-science is beginning to move away from seeing ADHD as just a problem with dopamine and/or nor-epinipherine, and is moving toward a better understanding of the brain as a network, and a network of relationships such as the relationship between dopamine, nor-epinipherine, the glutamate exitatory neurotransmitters which are about 30-35% of all neurotransmitters in the brain, and their relationship to ADHD.
And it seems that Intuniv makes more glutamate in the PFC.
Amy Arnsten, Ph.D., Arnsten Lab, Dept or Neurobiology at Yale University. According to its website, the Arnsten Lab "studies molecular influences on the higher cognitive functions of the prefrontal cortex (PFC), with the overarching goal of developing rational treatments for cognitive disorders and mental illness... Research has focused on how the catecholamines norepinephrine (NE) and dopamine (DA), powerfully and dynamically modulate PFC cognitive function and physiology through intracellular signaling mechanisms." The lab helped Shire Pharmaceuticals in the development of Intuniv for ADHD treatment.
The Arnsten Lab has been able show how the relationship between dopamine and nor-epinephrine, really the ratios of dopamine to nor-epinephrine, can impact and improve cognitive functions such as focus, memory, and attention. Too much or too little of either neurotransmitter decrease cognitive functions, both in terms of the performance of brain cells, and in the real world. But when the ratios and relationships are just right, performance is improved.
Their work, along with the work of many others, is often focused on the a2-receptor sites in the pre-frontal cortex. They have reported on the benefits of nor-epinepherine at these sites, and have also shown the benefits of stimulating these receptor sites with the medication guanfacine (intuniv).
It appears that guanfacine improved cognitive functioning in the pre-fronatl cortex. Other research has shown that small doses of methylphenidate actually impact the effects of nor-epinepherine in the pre-frontal cortex than the effects of dopamine in the PFC. This research has also shown that when the a2 receptors in the pre-fronatal cortex are blocked that the symptoms of ADHD can be created in a subject, including lack of self-control, impulsivity, and hyperactivity (Berridg et al, 2006)