Symptoms of caffeine withdrawal or substantial reduction in caffeine usage

1. Prolonged daily use of caffeine before substantial reduction or withdrawal from caffeine usage.
   

2. 3 or more of the following signs or symptoms within 24 hours after cessation of or reduction in caffeine use: a. Headache b. Marked fatigue or drowsiness c. Dysphonic mood, depressed mood, or irritability. d. Difficulty concentrating e. Flu-like symptoms (nausea, vomiting, or muscle pain stiffness)
   

3. The signs or symptoms are not attributed to the physiological effects of another medical condition (e.g., migraine, viral illness) and are not better explained by another mental disorder, including intoxication or withdrawal from another substance.