Caffeine blocks brain receptors that can dilate the blood vessels. This may lead to some withdrawal symptoms, such as headaches. Teas, energy drinks, colas and chocolate contain caffeine, though in smaller doses. People who consume those products regularly may have withdrawal symptoms when they try to stop. Children may also suffer from these withdrawal effects as much as adults, depending on how much they consume.
Severe, throbbing headaches, fatigue, sleepiness and inability to concentrate or focus on activities are common symptoms a person experiences when withdrawing from caffeine. The more caffeine consumed daily, the more difficult it is to stop and the more severe the withdrawal symptoms become, according to researchers at Johns Hopkins.
Nausea, vomiting and muscle pain or stiffness are other symptoms identified by researchers at Johns Hopkins. They analyzed 57 experimental studies and nine surveys on caffeine withdrawal. The research reveals that many people go back to using caffeine when they experience the withdrawal symptoms. In the experimental studies, the researchers found that 50 percent of the subjects had headaches and 13 percent had significant distress or difficulty in functioning. Even drinkers who had one small cup of coffee a day had withdrawal symptoms, but the people who drank more had more severe symptoms.
Other effects may include irritability, depression, anxiety and flu-like symptoms. High blood pressure and convulsions may also occur in people used to excessive caffeine. Drinking five to six cups of coffee a day can cause jitteriness and increased metabolic rate, according to Merck Source. There may also be waves of hot or cold sensations that sweep through the body.
Effects of giving up caffeine may last for two to nine days. The peak withdrawal symptoms usually occur between 20 to 48 hours following abstinence. The Johns Hopkins researchers advise a step approach to quitting caffeine. Instead of quitting right away, they recommend people gradually substitute decaffeinated products over time to slowly give up caffeine and avoid withdrawal symptoms. It will still be difficult, but the side effects may not be as severe by cutting back on consumption.