[Episodic headache, diminished performance and depressive mood]

By the example of two case reports, typical signs of caffeine withdrawal like headache, increased irritability, decreased performance and disturbed concentration are described. These symptoms occurred two times within one week in two healthy nonsmoking individuals volunteering in a scientific study including periods of 24 hours with standardized caffeine-free-diet. The two volunteers were used to a regular coffee consumption of eight cups per day (about 600 mg/day). Since caffeine obviously represents the most common psycho-stimulant worldwide and since even moderate coffee consumption may lead to dependence, withdrawal symptoms induced by sudden reduction of consumption or withdrawal of caffeine may occur more often than usually assumed.