ADHD Medication & Caffeine
Bedtime Calculator

How to read your estimated curve

This calculator models how stimulant medications and caffeine build up, peak, and gradually clear from your body over 24 hours.

• The Blue Curve (Medication): Shows your estimated active medication levels based on your formulation (Immediate Release, Extended Release, Biphasic, or Concerta OROS).
• The Amber Curve (Caffeine): Shows your active caffeine. Caffeine absorbed from coffee or energy drinks peaks in 30–60 minutes and gradually fades over several hours.
• The Dashed Line (Sleep Threshold): Indicates the estimated level below which most people can easily fall asleep, customized to your selected sensitivity.

What affects how fast you clear caffeine and medication?

Everyone's body processes stimulants at different speeds. Key real-world factors include:

• Body Weight: Your weight directly scales total body volume, determining how concentrated a given dose feels.
• Smoking & Vaping: Inhaled smoke speeds up how quickly your liver breaks down caffeine (clearing it up to 50% faster), though nicotine is still an evening stimulant.
• Vitamin C & High-Acid Drinks: Large doses of Vitamin C or acidic citrus juices increase how quickly amphetamines (Adderall / Vyvanse) are filtered out by the kidneys.
• Food & Heavy Meals: Taking certain medications with a high-fat breakfast can delay peak onset without changing the total amount absorbed.