Analysis of Caffeine in Coffee
Caffeine Sources Worldwide
Effects of Caffeine
Temperature Analysis
Extraction Method
Fragmentation Patterns
3-D Nature of GC/MS
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Caffeine Effects

The Effects of Caffeine in the Body

Caffeine is probably the most widely used drug.  It falls in the stimulant class, and effects the central nervous system.  The lethal dose of caffeine is too high to be of daily concern; the lethal dose is 170 mg/kg, or 12.5-14.6 g for an average adult male.  This corresponds to drinking about 80-100 cups of coffee in a short period of time assuming the entire amount was absorbed into the body.  It is rapidly absorbed through the stomach lining, and reaches the bloodstream in within 30-45 minutes.  It becomes equally distributed throughout the water of the body, later being metabolized in the liver and expelled via the kidneys.  The half-life of a dose of caffeine is 3.5-4 hours, though pregnant women generally maintain caffeine levels longer (half-life of 3-10 hours).  In particular, caffeine targets the cerebral cortex and the brain stem in the central nervous systems.  Doses of 100-200 mg result in increased alertness and wakefulness, faster and clearer flow of thought, increased focus, and better general body coordination.  It also results in restlessness, a loss of fine motor control, headaches, and dizziness.  In greater quantities (greater than 2 grams), insomnia, agitation, tremors, and rapid breathing begin to appear.  Caffeine stimulates the heart, dilates the vessels (increasing blood pressure), causes bronchial relaxation (can be used as an antiasthmatic drug), increases gastric acid production, and boosts the metabolic rate.  Caffeine also fits the definition of an addictive substance, with withdrawal symptoms, an increase in tolerance over time, and physical cravings.