Caffeine
Overdose
Caffeine overdose can result in a state of central nervous system over-stimulation known as caffeine intoxication, a clinically significant temporary condition that develops during, or shortly after, the consumption of caffeine. This syndrome typically occurs only after ingestion of large amounts of caffeine, well over the amounts found in typical caffeinated beverages and caffeine tablets (e.g., more than 400–500 mg at a time). According to the DSM-5, caffeine intoxication may be diagnosed if five (or more) of the following symptoms develop after recent consumption of caffeine: restlessness, nervousness, excitement, insomnia, flushed face, diuresis (increased production of urine), gastrointestinal disturbance, muscle twitching, rambling flow of thought and speech, tachycardia (increased heart rate) or cardiac arrythmia, periods of inexhaustibility, and psychomotor agitation.
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