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What to Expect When Starting Amphetamine/Dextroamphetamine

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Introduction

Adderall (amphetamine/dextroamphetamine) is a stimulant medication used to treat ADHD and narcolepsy. It works by increasing dopamine and norepinephrine activity in the brain, improving focus, attention, and impulse control. Unlike antidepressants, effects are often noticeable from the first dose, with dose optimization occurring over weeks.

Week-by-week timeline

Day 1-3

First Effects

Many people notice improved focus and reduced impulsivity on the first day. Common early side effects include decreased appetite, dry mouth, increased heart rate, and difficulty falling asleep. These are most noticeable when the medication is active (4-6 hours for immediate-release, 10-12 hours for XR).

Week 1-2

Adjusting to the Medication

Appetite suppression is typically strongest in the first week and may moderate somewhat. Your prescriber will assess whether the dose is appropriate. Take IR doses in the morning and early afternoon to avoid insomnia.

Week 2-4

Dose Optimization

Your prescriber may adjust the dose based on effectiveness and side effects. Finding the right dose for ADHD is individualized — too low gives insufficient benefit, too high increases side effects without improving function.

Month 1

Establishing a Routine

You should have a clearer picture of how Adderall is working for you. Discuss with your prescriber: Is the duration right? Is the dose right? Are you eating enough despite appetite changes? Weight monitoring is important.

Month 2-3

Long-Term Assessment

Continued benefit should be stable. Discuss any tolerance concerns with your prescriber. Many patients benefit from medication holidays (weekends, school breaks) to preserve appetite and growth in children. Stimulant therapy is often most effective combined with behavioral strategies.

When to call your doctor

Contact your healthcare provider if you experience:

  • Chest pain, shortness of breath, or fainting (cardiac events)
  • Heart rate above 120 bpm at rest or irregular heartbeat
  • Significant increase in blood pressure
  • Signs of psychosis: hallucinations, paranoia, unusual behavior
  • Severe agitation or panic
  • Thoughts of self-harm
  • Numbness or color changes in fingers or toes (Raynaud's phenomenon)

Tips for getting started

Take immediate-release Adderall in the morning and at lunchtime (no later than early afternoon) to avoid insomnia. Eat a nutritious breakfast before your first dose, even if appetite is low. Stay hydrated. Avoid caffeine, which can worsen anxiety and heart rate effects. Do not crush or chew extended-release capsules. Adderall is a controlled substance — store securely and never share. Your prescriber will monitor blood pressure, heart rate, weight, and height (in children).

Frequently asked questions

More about Amphetamine/Dextroamphetamine

References

  1. [Regulatory] FDA Label: Adderall (Mixed Salts of Amphetamine) https://www.accessdata.fda.gov/drugsatfda_docs/label/2017/011522s043lbl.pdf Accessed 2026-03-01.
  2. [Regulatory] NIH MedlinePlus: Dextroamphetamine and Amphetamine https://medlineplus.gov/druginfo/meds/a601234.html Accessed 2026-03-01.
  3. [Regulatory] FDA: ADHD Medications Safety Review https://www.fda.gov/drugs/drug-safety-and-availability/fda-drug-safety-communication-safety-review-update-medications-used-treat-attention-deficit Accessed 2026-03-01.

Written and fact-checked by PrescriptionDrugs.org Editorial Team

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