The thing about caffiene withdraw, however, is that most people think it should only last a few days. I'm seeing many anecdotal reports saying it can lasts 6 months or more. Futhermore, if you have a caffeine "sensitivity," they could last up to a year. However, I don't think caffiene withdraw explains "adrenal fatigue" by itself, I think that having caffiene withdraw adrenal fatigue prevents the HPA-axis from being able to recalibrate itself. So the withdraw has to be dealt with first, and could take a longer time than suspected. Headache A caffeine headache usually starts behind the eyes and then moves up the front of the head. Sleepiness This just isn’t your normal tiredness, this is sitting up straight but still can’t keep your eyes open tiredness. Irritability Everyone and everything gets on your last nerve. It’s best just to lock yourself in your room during this stage. Lethargy Forget about productivity at this stage because you’ll be unmotivated to do anything from the feeling of the lack of energy. Constipation Caffeine stimulates the bowel, so without its daily dose the colon gets a little cranky too. Depression Caffeine withdrawal can take away all hope for living. Temporary blues are one thing, but if you already struggle with depression this could be a big issue. Muscle Pain, Stiffness, Cramping If you normally have some caffeine prior to exercise then during caffeine withdrawal you could feel as though your muscles have weights strapped to them. Lack of Concentration Forget school, studying, brain surgery, or jet engine repair during this stage of withdrawal. Flu-like symptoms Stuffy nose, blocked sinuses, and sinus pressure have all been reported by people withdrawing from caffeine. Insomnia Some people actually can’t sleep when going through caffeine withdrawal. Nausea and Vomiting Some people can’t even think about food the first couple days of withdrawal which compounds the feeling of lethargy. Anxiety In some people, caffeine actually causes anxiety, but in others, withdrawing from the drug can cause feelings on anxiety and even panic attacks have been reported by some. Brain Fog Withdrawal can cause some people to experience brain fog which is described as the difficulty of having coherent thoughts, difficulty thinking, and the difficulty of doing common tasks. Dizziness Caffeine withdrawal can cause some people to lose their sense of equilibrium. Heart Rhythm Abnormalities Since caffeine also stimulates the heart muscle, some people experience changes in their heart rhythm during withdrawal. Both low blood pressure and even palpitations have been reported.