Cymbalta is used to treat major depressive disorder and general anxiety disorder. It is also used to treat a chronic pain disorder called fibromyalgia, and to treat pain caused by nerve damage in people with diabetes (diabetic neuropathy).
Caffeine-withdrawal headaches can last up to 48 hours and can be as intense as a migraine headache. Withdrawal symptoms can begin 12 to 24 hours after the last cup of coffee and can last up to 1 week. These symptoms can include lethargy, extreme nervousness, irritability, sweating, headaches and shakiness.
Experiment 4 manipulated duration of exposure to caffeine (1, 3, 7, or 14 days of 300 mg/day) and showed that caffeine withdrawal occurred after as little as 3 days of caffeine exposure, with a somewhat increased severity of withdrawal observed after 7 or 14 days of exposure.