Caffeine
StimulantsKey Benefits
How It Works
Caffeine blocks adenosine receptors (A1 and A2A), preventing sleepiness signals. This triggers increased dopamine, norepinephrine, and acetylcholine activity. It also mobilises fatty acids for fuel, enhances calcium release in muscles, and reduces perceived exertion during exercise.
Dosage & Timing
Recommended Dosage
100-400 mg daily (do not exceed 400 mg)
Best Time to Take
Morning to early afternoon. Avoid after 2pm (8-hour half-life). Pair with L-theanine.
Recommended Form
Caffeine anhydrous capsules (precise dosing) or coffee
Side Effects
Anxiety, insomnia, jitters, dependency, withdrawal headaches. Affects sleep architecture even if you fall asleep fine.
Drug Interactions
Enhances many drug effects. Interacts with MAOIs, some antibiotics, and cardiac medications. Reduces iron absorption.
What Does The Research Say?
The most widely consumed psychoactive substance. Well-established ergogenic aid (3-6mg/kg for performance). Tolerance develops rapidly. Cycling (2 weeks off every 8-12 weeks) maintains effectiveness. Genetics affect metabolism rate.
Where to Buy
Buy Caffeine on Amazon
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