Introduction
Most commonly used psychoactive substance in the world
Found in
Cacao beans
Coffee beans
Teas
Approximately 9% of individuals in the US have caffeine use disorder
Mechanism of action
Belongs to the methylxanthine category of alkaloids. (similar to adenosine)
Most of its effects are through adenosine receptors in the CNS
Non selective adenosine receptor antagonist.
Antagonism of the adenosine -2a receptor-> GABA reduction-> increased arousal .
Adenosine -2a forms a heteromer with dopamine receptors thus producing caffein’s dopaminergic effects.
Inhibiting adenosine-A1 receptors also causes sleep dysregulation
Non specific phosphodiesterase inhibitor
Pharmacology
80% metabolized to paraxanthine by CYP1A2
4-6 hour half-life
Overdose
Often related to energy drinks or caffeine supplements
Symptoms
Restlessness, anxiety, irritability
Increased temperature
Tachypnea
Tachycardia/irregular heartbeat
Headache
Dehydration
Withdrawal
Begins between 20-50 hours after last use and can last between 2-9 days.
Symptoms
Fatigue
Headache
Irritability
Pregnancy
Crosses placenta
High levels of ingestion have been associated with low birth rate, spontaneous abortion, and stillbirth
References:
“Addiction Psychiatric Medicine: A comprehensive Board Review” Colon-Rivera, et.al.