physiological and psychological. Symptoms of caffeine intoxication include: restlessness, nervousness, excitement, insomnia , flushed face, diuresis , muscle twitching , rambling flow of thought and speech , paranoia, cardiac arrhythmia or tachycardia , and psychomotor agitation , gastrointestinal complaints, increased blood pressure , rapid pulse , vasoconstriction (tightening or constricting of