"Caffeine, by any measure, is the world's most popular drug, easily surpassing nicotine and alcohol," said Bennett Alan Weinberg and Bonnie K. Bealer in The World of Caffeine.
However, unlike other drugs, caffeine is a highly unregulated and easily accessible drug; it's even part of normal life.
Every day, 80 percent to 90 percent of adults use caffeine. Most Americans start their day with a jolt of caffeine from either coffee or tea.
It is estimated that the average daily intake of caffeine in the United States is approximately 280 milligrams, which is the equivalent of two mugs of coffee or three to five bottles of soft drink.
While coffee and soft drinks are the most common sources of caffeine in America, reportedly half of those who use caffeine ingest it through various products, including chocolate and tea.
Caffeine use has become so widespread because it serves as a stimulant.
It increases metabolism, raises blood pressure and heart rate, and accelerates breathing. It also can offset the effects of sleep deprivation, while aiding concentration.
However, when caffeine intake is reduced, one may experience headaches, fatigue and decreased concentration.
According to a recent Johns Hopkins study, these effects are due to caffeine withdrawal. Some may even suffer from nausea or muscle pain.
These symptoms are generally more pronounced with increased caffeine consumption. Nevertheless, as little as one cup of coffee a day can lead to caffeine addition.
Dr. Roland Griffiths, professor of psychiatry and neuroscience at Johns Hopkins, and colleague Dr. Laura Juliano of American University reviewed more than a century and a half of caffeine withdrawal research, with the goal of establishing a framework for diagnosing this condition.
They conducted 57 experimental studies and nine survey studies on caffeine withdrawal. Upon examination of these studies, they were able to confirm the symptoms associated with the caffeine withdrawal syndrome.
The symptoms were divided into five groups: headache; fatigue or drowsiness; anxiety, depression, or unease; difficulty concentrating; and flu-like symptoms such as muscle aches, hot/cold spells, nausea or vomiting.
In the experimental studies, 50 percent of subjects experienced headaches. Additionally, 13 percent had severe symptoms, including functional impairments.
When the caffeine intake is reduced, blood pressure drops dramatically, causing an excess of blood in the head (though not necessarily on the brain), which is the leading cause in headaches.
Such headaches, known all too well among coffee drinkers, can last from two to nine days.
In most cases, such symptoms appeared 12 to 24 hours after the last dose of caffeine, with the greatest intensity during the first few days of reducing caffine intake.
The effects of caffeine withdrawal and can be alleviated with over-the-counter analgesics such as aspirin.
It can also be alleviated with caffeine intake, which causes people to continue regular use of caffeine.
Many analgesics, in fact, contain some caffeine. Griffiths, however, reassures those who wish to stop caffeine intake with good news.
The researcher was quoted as saying, "We teach a systematic method of gradually reducing caffeine consumption over time by substituting decaffeinated or non-caffeinated products. Using such a method allows people to reduce or eliminate withdrawal symptoms."
As a result of this study, caffeine withdrawal will be included in the in the new version of the DSM (Diagnostic and Statistical Manual of Mental Disorders), considered by many to be the definitive resource for diagnosis of mental disorders.
In addition, the diagnosis of this syndrome will be revised in the World Health Organization's ICD, or The International Statistical Classification of Diseases and Related Health Problems.
The results of this study were published in the October 2004 issue of the journal Psychopharmacology. The investigation was funded in part by the National Institute on Drug Abuse.
