

How does Qelbree work in your brain? A plain-English explanation of Viloxazine's mechanism of action, how long it takes, and how it differs from stimulants.
Qelbree (Viloxazine) works by increasing norepinephrine levels in the brain, which helps improve focus, attention, and impulse control in people with ADHD.
If you've been prescribed Qelbree or you're considering it, you might be wondering what it actually does inside your body. This guide explains the science in simple terms — no medical degree required.
To understand Qelbree, it helps to know a little about how ADHD affects the brain.
People with ADHD often have lower-than-normal levels of certain brain chemicals called neurotransmitters — particularly norepinephrine and dopamine. These chemicals help brain cells communicate with each other, and they play a key role in attention, focus, motivation, and impulse control.
Think of neurotransmitters like messages being passed between coworkers. In ADHD, some of those messages get recycled (pulled back) before the next person has a chance to read them. That's where Qelbree steps in.
Qelbree is classified as a selective norepinephrine reuptake inhibitor (SNRI). Here's what that means:
Think of it like putting a stopper in a drain. The water (norepinephrine) stays in the sink longer, giving your brain more time to use it.
While Qelbree primarily targets norepinephrine, research shows it also has effects on serotonin and dopamine activity in the prefrontal cortex — the part of the brain responsible for planning, decision-making, and attention. This multi-channel effect may explain why some patients respond well to Qelbree even when other non-stimulant medications haven't worked.
Unlike stimulant medications (which often work within hours of the first dose), Qelbree takes longer to build up in your system:
If you don't feel a difference right away, that's normal. Give it time, and stay in touch with your doctor about how you're feeling.
Qelbree is an extended-release medication, which means it's designed to release slowly throughout the day. You take it once in the morning and it provides coverage for the full day.
This is different from some stimulant medications that wear off after a few hours and may require multiple doses per day.
There are several things that set Qelbree apart:
For a detailed comparison, read our guide to Qelbree alternatives.
Qelbree is a strong CYP1A2 inhibitor, which means it can affect how your body processes other medications and even caffeine. If you drink coffee or take medications metabolized by CYP1A2, talk to your doctor about potential interactions. Our drug interactions guide has the full list.
Qelbree works by keeping more norepinephrine available in your brain, helping to improve the focus, attention, and impulse control that ADHD disrupts. It's not a stimulant, it's not a controlled substance, and it works differently enough from other options that it may be worth trying if other medications haven't been the right fit.
If you're considering Qelbree, talk to your doctor about whether it's a good option for you. And if you need help filling your prescription, Medfinder can help you find a pharmacy that has it in stock.
You focus on staying healthy. We'll handle the rest.
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