A 5 mg dose of immediate-release Adderall typically lasts 4 to 6 hours. This is the same general window as higher immediate-release doses, because changing the dose affects the intensity of the effect, not how long it lasts. If you’re taking the extended-release (XR) version, expect closer to 10 to 12 hours of coverage from a single capsule.
Immediate-Release vs. Extended-Release
Adderall comes in two formulations, and the one you have determines your timeline. Immediate-release (IR) tablets kick in within about 30 to 60 minutes and provide roughly 4 to 6 hours of symptom control. The drug reaches its peak concentration in your blood about 3 hours after you take it.
Extended-release (XR) capsules work differently. They contain two types of beads: one set dissolves right away, and the second set releases about four hours later. This mimics taking two IR doses spaced apart. Peak blood levels don’t arrive until about 7 hours after you swallow the capsule, and the effects stretch across most of the day. A single 20 mg XR capsule produces blood levels comparable to taking a 10 mg IR tablet twice, four hours apart.
Why 5 mg Doesn’t Wear Off Faster Than 10 mg
A common assumption is that a smaller dose must wear off sooner. It doesn’t. Research published in the Canadian Child and Adolescent Psychiatry Review confirms that higher doses produce a stronger peak effect but do not change the timing of that peak or the drug’s half-life. The 5 mg dose will feel less intense than a 10 mg or 20 mg dose, but the clock on how long it stays active in your body runs at the same speed. What you may notice is that the effects feel less noticeable toward the tail end of the window, simply because there’s less drug on board to begin with.
How Long It Stays in Your Body
The felt effects and the actual presence of the drug in your system are two different things. Adderall contains two forms of amphetamine. The d-amphetamine component has a half-life of about 10 hours in adults, meaning half the drug is still in your bloodstream 10 hours after you took it. The l-amphetamine component hangs around even longer, with a half-life of roughly 13 hours in adults.
In children aged 6 to 12, these half-lives are slightly shorter: about 9 hours for d-amphetamine and 11 hours for l-amphetamine. Adolescents fall in between, with half-lives of 11 hours and 13 to 14 hours for the two components. This means the medication is fully cleared from the body roughly two to three days after a single dose, even though the therapeutic effects end much sooner.
Factors That Shorten or Extend the Duration
Your body’s acidity plays a surprisingly large role. Amphetamine is cleared through the kidneys, and how acidic or alkaline your urine is dramatically changes how fast that happens. In one pharmacokinetic model, acidic urine conditions cut the total drug exposure nearly in half compared to normal conditions, while alkaline urine nearly doubled it. That’s a meaningful real-world difference.
What makes urine more acidic? High-protein diets, vitamin C supplements, cranberry juice, and certain metabolic conditions like diabetes or obesity all tend to lower urine pH. On the other side, vomiting, urinary tract infections, and some medications can make urine more alkaline, which slows the drug’s clearance and extends its effects. If you notice your Adderall seems to wear off unusually fast on some days, your diet that day could be a factor.
Other variables include your weight, liver function, kidney health, and whether you’ve eaten recently. Taking Adderall on an empty stomach generally leads to faster absorption and a quicker onset, though it doesn’t significantly change the total duration.
The Comedown Window
Many people experience a “crash” as the medication wears off, especially with immediate-release formulations. This can feel like a sudden dip in focus, energy, or mood. According to Cleveland Clinic, this crash typically begins 30 to 60 minutes before the medication fully leaves your system and lasts about an hour. For a 5 mg IR dose, that means you might start feeling a dip around the 3.5 to 5 hour mark.
The crash tends to be less pronounced at lower doses like 5 mg compared to higher ones, because the gap between “medicated” and “unmedicated” is smaller. Some people on 5 mg barely notice a comedown at all. If you do experience one, eating a meal and staying hydrated around the time the dose is expected to wear off can help smooth the transition.
Why 5 mg Is a Common Starting Dose
For Adderall XR, 10 mg once daily is the standard starting dose for children aged 6 to 12. But FDA labeling notes that clinicians can start at 5 mg when a lower initial dose seems appropriate, and 5 mg is the recommended dose for children with severe kidney impairment. For immediate-release Adderall, doses are often adjusted in 5 mg increments on a weekly basis until the right balance of symptom control and side effects is found.
At 5 mg, you’re at the lowest available dose. If the effects feel too mild or fade before you need them to, the typical next step is a dose increase rather than taking a second dose on your own. If you’re finding 4 to 6 hours isn’t enough coverage, an extended-release formulation may be a better fit for your daily schedule.