If you or your autistic teen is dealing with meds and learning to drive, you’ve probably heard some version of this:
“Let’s try this medication and see what happens.”
Then you wait a few weeks.
If there are side effects—you switch.
If nothing happens—you adjust.
And then… you do it all over again.
I’m not making this up—it’s actually how psychiatry has worked for decades.
Why? Because people respond very differently to the same medication.1
But now there’s another option in the mix: pharmacogenomic testing.
So—can testing tools like GeneSight and similar pharmacogenomic panels help you skip the guessing game, and how do they do that?
How these tests work
Tests like GeneSight look at specific genes—especially ones involved in how your body processes medications.
A lot of this comes down to enzymes like CYP2D6 and CYP2C19 (who names these things, lol?), which affect how quickly your body breaks down a drug or builds it up in your system.
Research suggests these genetic differences can affect things like drug levels, effectiveness, and side effects.2
This means your DNA might help predict how your body handles a medication, with “might” being the operative word here.
So why are people excited about this?
In theory, this could reduce side effects, avoid medications your body doesn’t handle well, and hopefully save months and months of time trying drugs that were never going to work for you anyway.
And yes—some studies do support that idea.
A 2024 systematic review found that pharmacogenetic-guided prescribing either nudged outcomes in the right direction or was no different than usual care. The downside? It wasn’t clearly better across the board.1
These tests mostly predict how your body metabolizes a drug, but they can’t reliably predict whether the drug will work for you.
At this point you might be thinking, ‘so… is this even worth it? Honestly, the jury’s still out—but I’m staying optimistic. I’ve heard enough people say it helped them that I’m going to stick with the opinion that it can probably help.
So why are we still stuck with trial and error?
Even with genetic testing, a lot of other things still affect how a medication works—your brain chemistry, your diagnosis, your environment, other meds, timing… all of it plays a role.
Genetics matters—but it’s only one piece of a pretty complicated puzzle. That’s why results can vary so much. Making sense of the results isn’t always straightforward—that’s where your doctor really matters.3
I took the GeneSight test a few years ago when I needed an antidepressant for short-term use, and my doctor was so thoughtful with the results. I think it helped me avoid whole categories of meds that probably wouldn’t have worked for me because I also have some anxiety which can complicate things. (Anxiety is really common in autism families.) We landed on one that worked on the first try. My cousin, on the other hand, used similar testing—and it still took several tries.
Why this matters for driving
If you’re learning to drive, medications don’t play around—they can affect your energy levels and alertness, focus, and reaction time. (All while you’re going 60 miles per hour, I might add!)
So─is it worth it?
Here’s the deal─it can be a helpful tool, but it’s not a guarantee.
Like GPS, it helps you navigate—but you’re still in the driver’s seat dealing with whatever comes up.
If you’re aiming for safe, confident driving, the goal isn’t just ‘pick the right medication instantly,’ it’s more about learning how your brain and body respond—and adjusting as you go.
Because even when genetics play a role, what you actually feel day to day still matters more.
Check out my companion blog piece that compares the pharmacogenomic testing available these days, Comparing Pharmacogenomic Testing Companies: A Brief Overview, here.
Join me next time as I dig into the next class of medications that can affect driving: antidepressants.
Want to See the Science?
- A systematic review of pharmacogenetic testing to guide antipsychotic treatment. Khani NS, Hudson G, Mills G, et al. Nat Ment Health. 2024;2(5):616–626. doi:10.1038/s44220-024-00240-2 (PubMed)
- Genetic Testing for Antipsychotic Pharmacotherapy: Bench to Bedside. Koola MM. Behav Sci (Basel). 2021;11(7):97. doi:10.3390/bs11070097 (PMC)
- Pharmacogenetic tests for antipsychotic medications: clinical implications and considerations. Eum S, Lee AM, Bishop JR. Dialogues Clin Neurosci. 2016;18(3):323–337. doi:10.31887/DCNS.2016.18.3/jbishop (PubMed)
A systematic review of pharmacogenetic testing to guide antipsychotic treatment. Khani NS, et al. PMCID: PMC11088993. (PMC)