Two people take the same dose of the same drug. One feels nothing. The other has side effects within an hour. A lot of that difference is written in your genes, specifically in the enzymes your liver uses to process medications. The study of it is called pharmacogenomics, and it's one of the most practically useful things a genome can tell you.
Your body processes drugs at different speeds
Most medications are broken down by a family of liver enzymes. The genes that build those enzymes come in common variants, and those variants change how fast the enzyme works. GeneLab reports this as a metaboliser status for each relevant gene:
- Normal metaboliser, the enzyme works as expected; standard dosing usually applies.
- Slow (or poor) metaboliser, the drug clears slowly, so it can build up; a standard dose may feel like a high dose.
- Fast (or rapid) metaboliser, the drug clears quickly, so a standard dose may be less effective.
A concrete example
Take CYP2D6, an enzyme involved in processing many antidepressants and painkillers. If you're a poor metaboliser, a standard SSRI dose can sit in your system longer than intended. That doesn't mean the drug is wrong for you, it means the starting dose and the timeline are worth a conversation. That conversation is exactly what a pharmacogenomic report is for.
Never change a prescription on your own based on a genetic report. Pharmacogenomics informs a conversation with your prescriber, it doesn't replace one.
Why it's worth knowing before you need it
The useful thing about pharmacogenomics is that it doesn't expire. Your metaboliser status is the same whether you learn it today or the day you're prescribed something new. Knowing it ahead of time means that when a prescription does come up, you and your clinician already have the information in hand, rather than discovering a slow-metaboliser effect through trial and error.
How GeneLab reports it
On the Advanced Medical and Max tiers, your report includes a pharmacogenomics table: medication class, the gene involved, your metaboliser status, and a short note. On the Max Plan, you can also ask the Health AI Assistant about any flag in plain language, and it will cite the exact gene behind its answer.
It's a small section of a genome report, but often the most immediately actionable one. See how it looks in a sample report ›