Caffeine is a substance that is similar in structure to adenosine, which is one of the main molecules that control the function of the brain and the nerves. When the intake of caffeine is increased, caffeine binds with the receptors that usually bind with adenosine. Therefore, adenosine cannot play its functions. In order to avoid that, our body increases the number of receptors, creating enough of them for both adenosine and caffeine.

However, when the regular intake of caffeine is stopped, adenosine cannot fill all the receptors, and the body interprets this as insufficient adenosine. The symptoms that might appear include: headache, irritability, an inability to concentrate, drowsiness, insomnia, and pain in the stomach, upper body, and joints. These symptoms usually last from one to five days, which is the time needed for the receptors to return to normal levels. Anxiety might be present, too.


The heartburn, stomach pain, and chest problems might be related to certain of the conditions that can be caused over longer periods of increased caffeine intake, such as: peptic ulcers, erosive esophagitis, and gastroesophageal reflux disease. However, any of these conditions might be caused by a variety of other causes and needs to be examined separately by a specialist for the upper gastrointestinal tract. If any of the previously mentioned disorders is found, than adequate therapy might be recommended (antacids, proton-pump inhibitors). As for the caffeine intake, it is highly probable that the doctor would recommend decreasing it. He might only modulate the speed with which you should have your caffeine withdrawal.