Caffeine Flashcards
most commonly consumed psychoactive drug in the world
Caffeine
Caffeine
in the U.S.- consumed by 80% of the population
caffeine is found in
coffee, tea, cola, and chocolate, in prescriptions and OTC medications
caffeine safety?
is safe and can be added to anything
xanthines
3 types of related alkaloids from plants
1) theophylline
2) caffeine
3) theobromine
Absorption of Caffeine
oral caffeine is rapidly and completely absorbed
- peak blood levels within 30-45 mins absorption over 15-20 mins
- freely and equally distributed throughout the body (including brain)
- crosses placenta to fetus
Effects of Caffeine
~relax smooth muscles
—dilation of the lungs
~strengthens striated muscles
~constriction of blood vessels in the brain, dilation of blood vessels in the body
Mechanism of action (CNS)
caffeine exerts variety of effects at different doses
- epinephrine release, enhance functioning of dopamine
- Adenosine
Adenosine
neuromodulator of several NT systems
- majority of adenosine effects are sedating, depressing, and anticonvulsant
- caffeine blocks this inhibitory effect
psychostimulant effects of caffeine
-alertness, wakefulness, etc
heavy consumption (12 or more cups/day or 1.5g caffeine)
-agitation, anxiety, tremors, rapid breathing, insomnia
LD50 caffeine
10g 75-100cups of coffee
Caffeine and cognitive performance
ingestion of 1-3 cups of coffee increased capacity for sustained attention and decreased reaction time
- most effective in chronic users
- most effective if subjects are fatigued
tolerance and dependence of caffeine
- develops slowly
- caffeine use disorder is an experimental disorder in the DSM V
Primary withdrawal of caffeine
headache
- usually starts within 12-24 hours after cessation of coffee
- increased fatigue
- strongest during first 2 days, last for 5-6 hours