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Does anyone have any experience with genetic testing for ADHD meds, and/or have any opinions on its reliability?

My DS12 has ADHD Inattentive Type. To try and avoid medication trial and error, we had gene testing done early last year. Results showed not one single medication in his "green bin" as it's called. Only one was in the middle tier (yellow). All the stimulants--yes, all of them--were in the red. The pediatrician gave us a very pat "We can't try stimulants" and told us our only option was to try the medication in the yellow bin--Guanfacine. We started that medication last February, and after a period of horrible drowsiness and then three more weeks of waiting, it finally kicked in. His teacher said he was more with it, his test scores shot up in his trouble area (math), he was more able to keep everything together at home, could write better, could complete his thoughts both verbally and on paper. I wouldn't call it a miracle, but we could tell that it helped. That was the end of 5th grade. In the beginning of 6th grade, he tested all the way out of 6th grade math and was placed in advanced 7th grade math. All was still well at school and at home, relatively. However, as the year went on, we noticed that he got less and less "with it". Grades dropped, memory disappeared, etc. Last week, his ped advised that we increase the dose, because he's grown 5 in and gained 15 lbs since he started the medication. We are now fighting the drowsiness again and enduring the three week wait period to see if it helps.

While all of this is going on, I'm sitting here reading about stimulants and how, if they work for you, the benefit is immediate and very noticeable. And I'm wondering if we should try one of the stimulants that is on his gene testing red list. There are different clinical considerations for each med, and some sound less threatening than others. One of them just says he may require a lower dose to be effective, one says it may be difficult to know how to adjust dosage. Those just sound like minor complications, not something that would completely rule a medication out. I'm going to talk to his ped next week at his checkup and ask if we can't just try one of those, because watching my very bright (gifted, even) child struggle is heartbreaking.

Has anyone done genetic testing for this purpose? If so, were the results hard and fast reliable?

First off, we have not done this. But I do have some thoughts:

What were the contraindications for stimulants? Were they expected to have low therapeutic effectiveness, or to have serious side effects? There's a big difference between those two rationales for being not recommended. Some of the serious considerations against psychostimulants for certain individuals include suicidality (e.g., in persons at risk for mood disorders, especially depression), and substance abuse (in persons at risk for addictive behavior). Those are factors that often would also be picked up in the family medical history. When you read about common side effects of psychostimulants for the general population, these serious ones might not be as relevant.

As to the genetics, there is an increasingly rich pool of big data-generated correlations between certain profiles and certain complex traits. But like any emerging technology, there is also still uncertainty. Is it hard and fast reliable? Depends on your personal definition of hard and fast, range considered reliable, and assumption of risk.

The clinical considerations differed depending on the medication. I picked up a clearer copy of the report from our doctor's office today. Even the medication he takes, Guanfacine, has a clinical consideration 4 (see below) but it has worked pretty well for him in the past. The only medication that lists a risk of more side effects is Strattera. If I'm putting much faith in this report, Adderall, Dexedrine, or Vyvanse may be worth at least a try at a low dose. I've also done some reading today and there is one study that lends some support to the strategy of using Guanfacine along with a stimulant.

Clinical Considerations:
1. Serum level may be too high, lower dose may be required.
3. Genotype is associated with reduced therapeutic response to this drug.
4. Genotype suggests a reduced response to this medication.
5. Genotype indicated patient may experience increased side effects, but also increased efficacy.

Adderal: 1,3
Dexedrine: 1,3
Vyvanse: 1,3
Kapvay: 1,4
Strattera: 1,5
Focalin: 3,4
Ritalin, Concerta: 3,4

Going back to something I said in another thread:

In other words, I wouldn't put any real value on the gene test. At best they can tell you that your DS has somewhat elevated odds of certain reactions compared to the population at large. They still can't tell you what specific outcomes your DS will experience.

I'll risk embarrassment here and admit that I had to look up phrenology. I get it now... I am becoming more skeptical of the gene testing--in his case anyway--after picking up the clearer report and seeing that the medicine he is currently taking has CC 4 (reduced response), and that it did not have any CC related to side effects. The primary side effect, drowsiness, was horrible when he first started the medication, and for five days with this dose increase it was horrible again. And he did respond quite well to it until he had a huge growth spurt. I'm becoming more willing to add a stimulant to his regimen; at the very least we will know that we tried all tools available to help him be his best. I know it has to be incredibly frustrating for him to be floundering. This is a kid who, at four years old in pre-k, was found beside the trash can in tears because he was trying to throw away a plastic container from his lunch. The container had a recycle symbol on it, but there was no recycle bin, and he was so distraught because he has always been compelled to do what should be done, period. The failures on the executive function side have to be especially frustrating for a kid who has always desperately tried to do the right thing.

Thanks for your input!

The genetic test for medication efficacy has been pretty accurate for us. We actually tried the meds first and then got the results back, so it basically explained what we were seeing. It will depend on what your variances actually were, but here’s what happened for us. DD is resistant to methylphenidate based stimulants through two pathways. For her, when we tried long acting methylphenidate, which should have an onset within an hour and an effect for about 8-9 hours, we saw that it took 3-4 hrs for onset. Duration from time of ingestion was about the same, meaning we only saw about 3.5-4 hrs of effect. Increasing the dose caused emotional lability but didn’t increase the duration of effect.
HTH. Happy to answer any questions.

I'm not sure a common and expected effect like initial drowsiness would even be on the report. I would assume the report would be about long-term side effects that would prevent a person from continuing on a medication--not just the first couple weeks.

FWIW both my kids take guanfacine and a stimulent. For my daughter, the stimulent is very effective, but gave her a lot of anxiety in higher doses, so we went with a lot dose + guanfacine. My son just didn't get much help with stimulents, but the guanfacine was noticibly useful to him.

We have not tried genetic testing. Our prescribing specialist didn't think it was reliable enough to bother with.

We had this done and it showed that the methylphendiate drugs were in that "yellow" category. She had tried those and they did help, but not as much as one would expect. She also had a lot of moodiness. Interestingly almost all of the antidepressants came out on the "red" list, with the warning that they had an increased risk of side effects. So I'm glad we never went down the road of trying antidepressants that are normally prescribed for kids, and risked watching her get moodier and moodier rather than improving. I think the gene testing may be useful for ADHD meds if you have tried various meds and had nasty side effects or just couldn't find anything that worked. It can lead a person in the right direction, but it's not foolproof. Guanfacine was on her "yellow" list and she has tried it, and I never felt like it did that much. I read somewhere that it is helpful in kids but not adolescents/adults.