How long is Vyvanse effective?

Vyvanse is a stimulant medication used to treat attention deficit hyperactivity disorder (ADHD) and binge eating disorder. It’s active ingredient is lisdexamfetamine, which gets converted by the body into dextroamphetamine once absorbed. This helps improve focus, concentration, and impulse control in people with ADHD. Vyvanse is a long-acting medication with effects that can last 10-14 hours.

How does Vyvanse work?

Vyvanse contains the prodrug lisdexamfetamine, which is inactive on its own. Once absorbed in the gastrointestinal tract, enzymes convert lisdexamfetamine into the active drug dextroamphetamine. Dextroamphetamine is a central nervous system stimulant that increases levels of dopamine and norepinephrine in the brain. This results in improved focus and concentration, decreased impulsivity, and increased energy and motivation.

The conversion of lisdexamfetamine into dextroamphetamine occurs at a steady rate over time. This results in a gradual onset and long duration of effects from a single dose. Peak plasma concentrations of dextroamphetamine occur around 3.5 hours after taking Vyvanse.

How long does Vyvanse last?

On average, the effects of Vyvanse can last 10 to 14 hours. However, this can vary from person to person based on factors like:

  • Age
  • Body composition
  • Metabolism
  • Medications taken with Vyvanse
  • Food intake
  • Dosage of Vyvanse

In clinical trials, the duration of action of Vyvanse was measured by looking at when people first reported feeling the medication working compared to when people reported the effects wearing off. On average:

  • Vyvanse started working in about 2 hours
  • Peak benefits were experienced around 4 hours after taking it
  • Effects wore off approximately 12 to 14 hours after taking it

This shows that on average, Vyvanse remains effective for 10 to 12 hours. However, some people may experience effects for slightly shorter or longer durations.

Early effects (1-4 hours)

In the first few hours after taking Vyvanse, you’ll gradually start experiencing the benefits. This includes:

  • Improved focus and concentration
  • Reduction in ADHD symptoms like hyperactivity and impulsiveness
  • Suppressed appetite
  • Increased motivation and energy

These early effects represent the onset of action as the Vyvanse gets absorbed and converted into dextroamphetamine. The medication reaches peak levels approximately 2 to 4 hours after you take it.

Peak effects (4-8 hours)

Vyvanse is most effective approximately 4 to 8 hours after you take it. This is when you’ll experience maximum benefits in terms of:

  • Focus and concentration
  • Impulse control
  • Task completion
  • Memory
  • Motivation

During these peak hours, ADHD symptoms should be well controlled. You may feel very focused and productive during this time period.

Late effects (8-14 hours)

In the last few hours before Vyvanse wears off, you’ll continue experiencing benefits but they may start to decrease in intensity. Late effects can include:

  • Mild focus and concentration
  • Some suppression of hyperactivity/impulsivity
  • A return of appetite
  • Less motivation and energy compared to peak

Vyvanse tapers off gradually as the dextroamphetamine gets eliminated from your body. By 14 hours, most people no longer feel the medication working.

Factors affecting duration of Vyvanse

While Vyvanse may last 10 to 14 hours on average, several factors can influence how long it remains effective for you personally:


Younger children tend to have a decreased duration of action compared to teenagers and adults. This is because metabolism is faster in childhood. Vyvanse duration is likely to increase as a child gets older.

Body Composition

People with higher percentages of body fat may metabolize Vyvanse more quickly. This can result in shorter duration of effects compared to leaner individuals.


Certain medications can impact absorption and metabolism of Vyvanse, leading to changes in duration of action. For example, urinary alkalinizers like sodium bicarbonate can make Vyvanse less effective.

Food Intake

Consuming protein-rich foods with Vyvanse may help extend its duration. Having an empty stomach when you take it can decrease duration.


Higher dosages of Vyvanse tend to have longer-lasting effects compared to lower dosages. However, dosing is individualized based on clinical response and side effects.

Individual Factors

Due to differences in metabolism from person to person, some individuals may experience shorter or longer duration of action than average. The same person can also have varying durations of effects each day.

How to extend the effects of Vyvanse

If you want to make your Vyvanse last longer, here are some tips that may help:

  • Take Vyvanse early in the day – this prevents sleep disturbances from it wearing off too late
  • Avoid acidic beverages like orange juice – they can speed up elimination
  • Eat a protein-rich meal with your dose – this helps absorption
  • Stay hydrated and drink plenty of water – prevents dry mouth and headaches
  • Take an approved booster like dextroamphetamine later in the day
  • Talk to your doctor about trying a higher dose

However, keep in mind that tolerating overly extended effects can lead to insomnia, irritability, and emotional ups and downs as the medication wears off. Work closely with your prescriber to find the ideal dosing schedule and duration of action for your needs.

Vyvanse Crash

As Vyvanse wears off, some people experience a “crash” where they feel tired, depressed, irritable, anxious or hungry. This represents the downswing after the stimulant effects fade away. A crash can occur any time after peak effects, but is more common toward the end of the dose.

To minimize crashes, follow the same tips for extending Vyvanse duration above. Having an overlapped dose by taking an additional booster medication may prevent crashes by creating a more gradual taper.

If you do experience a crash, try to cope by:

  • Exercising to boost endorphins
  • Eating a healthy snack to stabilize blood sugar
  • Getting good rest and sleeping it off
  • Using relaxation techniques like deep breathing

If crashes persist and affect your daily functioning, discuss adjusting your Vyvanse schedule with your doctor.

How long Vyvanse stays in your system

Vyvanse has an extremely long half-life – the time it takes for your body to eliminate half of the drug dose. Vyvanse’s half-life is approximately 13-14 hours in adults and 11 hours in children.

Four to five half-lives are required for a medication to be fully eliminated from your system. Therefore, Vyvanse can stay in your system for an estimated:

  • 55-70 hours in adults
  • 44-55 hours in children

However, Vyvanse may be detectable in urine for 1-4 days after stopping due to the long half-life. Detection times in saliva and hair will be even longer.

Starting and stopping Vyvanse

When starting Vyvanse, it may take several weeks to reach optimal effects. Doses often need gradual adjusting to find the ideal amount unique to each patient. Always work closely with your prescribing doctor when starting Vyvanse to limit side effects.

If stopping Vyvanse, never do so abruptly without medical supervision. This can lead to fatigue, depression, irritability, and changes in blood pressure and heart rate. Vyvanse should be tapered off slowly over weeks to months to prevent withdrawal symptoms.


In summary, Vyvanse can remain effective for 10 to 14 hours on average. However, effects may last for shorter or longer periods based on your individual metabolism and dosage. Timing your dose right, modifying dietary intake, staying hydrated, adding a booster, and adjusting the Vyvanse dosage can all help prolong its benefits. Be aware of potential crashes as the stimulant effects wear off. Regular follow-ups with your prescriber helps ensure Vyvanse works optimally at the right dose and schedule tailored for your needs.

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