Amphetamine/Dextroamphetamine works by increasing the levels of two key brain chemicals — dopamine and norepinephrine — that help you focus, pay attention, and control impulses.

That's the one-sentence version. If you want to understand what's actually happening in your brain when you take this medication — and why it helps with ADHD — keep reading. We'll break it down in plain English, no medical degree required.

What Amphetamine/Dextroamphetamine Does in Your Brain

To understand how this medication works, it helps to know a little about how your brain communicates.

Your brain cells (neurons) talk to each other by releasing chemical messengers called neurotransmitters. Think of neurotransmitters as tiny text messages sent between brain cells. Two of the most important ones for focus and attention are:

• Dopamine — Involved in motivation, reward, and the ability to sustain attention on a task. People with ADHD often have lower-than-normal dopamine signaling.
• Norepinephrine — Involved in alertness, arousal, and the ability to respond to important stimuli. It helps your brain filter out distractions.

In people with ADHD, the brain doesn't produce or use these neurotransmitters efficiently. It's like having a weak signal — the messages between brain cells get lost or arrive too slowly.

How the Medication Fixes the Signal

Amphetamine/Dextroamphetamine does two main things:

1. It increases the release of dopamine and norepinephrine. Think of it like turning up the volume on those chemical messages. The medication causes your neurons to push more dopamine and norepinephrine out into the spaces between brain cells (called synapses).
2. It blocks reuptake. Normally, after a neurotransmitter delivers its message, it gets recycled (pulled back into the neuron that released it). Amphetamine/Dextroamphetamine slows this recycling process, so dopamine and norepinephrine stay active longer — like keeping a text message on the screen instead of letting it disappear.

The result? More dopamine and norepinephrine are available for longer, which strengthens the brain's ability to focus, filter distractions, and control impulses.

The Two-Part Formula

Amphetamine/Dextroamphetamine is a combination of two slightly different forms of amphetamine:

• Dextroamphetamine (75%) — The more potent form. It primarily affects dopamine and is largely responsible for the focus-enhancing effects.
• Levoamphetamine (25%) — Affects norepinephrine more strongly. It contributes to alertness and physical energy.

This 75/25 blend is what makes Adderall unique — it delivers both rapid cognitive focus and sustained alertness.

How Long Does It Take to Work?

The onset depends on which formulation you take:

• Immediate-release (IR): You'll typically start feeling effects within 20-30 minutes. Peak effects occur around 1-3 hours after taking it.
• Extended-release (XR): The capsule contains two types of beads — half release immediately and half release about 4 hours later. You'll feel initial effects within 30-60 minutes.
• Mydayis: Contains three types of beads for even longer coverage. Onset is similar to Adderall XR.

How Long Does It Last?

• Immediate-release (IR): About 4-6 hours per dose. Most patients take it 2-3 times daily.
• Extended-release (XR): About 10-12 hours. Taken once daily in the morning.
• Mydayis: Up to 16 hours. Designed for patients who need coverage into the evening.

Duration varies from person to person depending on metabolism, body weight, stomach acidity, and other factors. If you feel the medication wearing off too quickly or lasting too long, talk to your doctor about adjusting the formulation or dose.

What Makes It Different from Similar Medications?

Amphetamine/Dextroamphetamine isn't the only stimulant used for ADHD. Here's how it compares to the most common alternatives:

• Lisdexamfetamine (Vyvanse) — A prodrug of Dextroamphetamine, meaning your body has to convert it before it becomes active. This gives it a smoother onset and lower abuse potential, but it only comes in one formulation (once-daily capsule).
• Methylphenidate (Ritalin, Concerta) — Works differently: it blocks dopamine and norepinephrine reuptake but doesn't increase their release like amphetamines do. Some patients respond better to one class than the other.
• Dextroamphetamine (Dexedrine) — Contains only the dextro-isomer (no levoamphetamine). It may have a slightly different side effect profile — some patients find it smoother, while others prefer the energy boost from the levo component.
• Atomoxetine (Strattera) — A non-stimulant that selectively blocks norepinephrine reuptake. Not a controlled substance. Often tried when stimulants aren't appropriate or cause too many side effects.

Final Thoughts

Amphetamine/Dextroamphetamine works by boosting the brain's natural focus chemicals — dopamine and norepinephrine. It's not creating something new; it's amplifying signals that are already there but aren't strong enough in people with ADHD.

Understanding how your medication works can help you use it more effectively and have better conversations with your doctor. If you're curious about side effects or drug interactions, we've covered those too.

Need to find Amphetamine/Dextroamphetamine in stock? Medfinder can help you locate a pharmacy near you.