Caffeine-induced psychosis
CaffeineWeb.com
"If a person were injected with 500 milligrams of caffeine [less than the dosage in some 16-ounce brews], within about an hour he or she would exhibit symptoms of severe mental illness, among them hallucinations, paranoia, panic, mania, and depression. But the same amount of caffeine administered over the course of a day only produces the milder forms of insanity for which we take tranquilizers and antidepressants."
"For five years I worked in a team practice with physicians and psychotherapists. Often, the psychological evaluation would include one or more anxiety syndromes, and the recommendation was for counseling. I would point out that the person was consuming excessive amounts of caffeine and request a trial month off caffeine prior to therapy sessions. In about 50% of cases, the anxiety syndrome would resolve with caffeine withdrawal alone."
"In over a decade of practice as a clinical nutritionist, I have seen firsthand, with thousands of clients, that caffeine is a health hazard. Anxiety, muscle aches, PMS, headaches....However, if that's all caffeine has done to you, you're lucky. What about people misdiagnosed as neurotic or even psychotic, who spend years and small fortunes in psychotherapy--all because no one asked them about their caffeine intake?"
Nutritional biochemist Stephen Cherniske, Author, Caffeine Blues: Wake Up to the Dangers of America's #1 Drug
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"Coffee excesses can elicit symptoms of violent behavior in some persons; but what a feeling of relief to both physician and patient to see the symptoms completely disappear on the physician's order to stop drinking coffee...."
"The symptoms vary with acquired or inborn tolerance, but in general the patients may complain of light headedness, dizziness, breathlessness, chest discomfort, nervousness, irritability, tremulousness, muscle twitching, tension headache, insomnia (difficulty in getting to sleep or staying asleep), psychoneurosis (anxiety), lack of appetite, loss of weight, restlessness, silliness, elation, euphoria, confusion, disorientation, excitation, and even violent behavior with wild, inanic screaming, kicking and biting, progressing to semi-stupor."
"The symptoms of caffeine overdose are varied and bizarre and could be easily misinterpreted....Coffee overindulgence is overlooked many times because the bizarre symptoms may resemble and masquerade as an organic or mental disease."
Sidney Kaye, Ph.D, of the Institute of Legal Medicine
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"The potential for caffeine intoxication to cause clinically significant distress is reflected by the inclusion of caffeine intoxication as a diagnosis in DSM-IV (Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition)(American Psychiatric Association, 1994) and in ICD-10 (International Statistical Classification of Diseases and Related Health Problems, Tenth Edition)(World Health Organization)."
"Studies have shown that high dietary doses of caffeine (200 mg or more) increase anxiety ratings and induce panic attacks in the general population. In the United States the average per capita daily intake among adult caffeine consumers is 280 milligrams (the equivalent of 17 ounces of brewed coffee)."
"Although highly anxious individuals tend to be more likely to limit their caffeine use, not all individuals with anxiety problems naturally avoid caffeine, and some may fail to recognize the role that caffeine is playing in their anxiety symptoms."
"It has been noted that caffeine intoxication can occur in someone who has been using caffeine for many years with no prior apparent problems."
Roland R. Griffiths, Ph.D, The Johns Hopkins University School of Medicine
Professor of Behavioral Biology, Department of Psychiatry & Behavioral Sciences
Professor of Neuroscience, Department of Neuroscience
Formerly Research Chief, Department of Psychiatry, Baltimore City Hospitals, Baltimore, MD
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"Diagnosis of any caffeine-related disorder begins with clinical awareness. Beverage caffeine is such a common component of social activity that its consideration as a psychostimulant often is neglected."
"Too many clinical histories fail to record caffeine use. A complete caffeine history includes doses associated with beverages and medications....The observable signs associated with caffeine consumption are dose dependent. For most individuals who consume caffeine in the average range, the physical stigmata will include arousal signs. Expect to see nervousness, elevated heart rate, increased respiratory rate, flushed face, and an exaggerated startle response. Caffeine is a mild diuretic and may contribute to vague gastrointestinal complaints. In rare cases where an individual's dose exceeds 1 gram per day, the picture changes. Gross muscle tremors, highly disorganized speech, and possible arrhythmias herald a more sinister outcome." [CaffeineWeb note: One gram has long been considered the toxic dose of caffeine, but it may not be as rare as supposed. A recent University of Florida study published in the Journal of Analytical Toxicology found that two 16 oz. Starbucks coffees may contain in excess of one gram.]
R. Gregory Lande, DO, FACN, Deputy and Director of Professional Services, Department of Clinical Administration, William S. Hall Psychiatric Institute, University of South Carolina
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Restless legs is a syndrome which may be associated with anxious and depressed as well as other clinical states. Dr. Lutz, in "Restless Legs, Anxiety and Caffeinism" (1978), suggests that this syndrome is primarily caused by caffeine. Anxiety is not a causative factor. Caffeine stimulates the nervous system and has a direct contractile effect on striated muscle. This is reflected in anxiety, depression, and insomnia: and the heightened proprioceptive awareness may result in restless legs. This manifestation consists of nervousness and movement of legs as a result of a distressing creeping sensation. Its symptoms are most obvious at night when the patient is trying to be still, and results in insomnia. Dr. Lutz describes cases of this disorder in detail and cites examples, all of which were alleviated when caffeine was removed from the diet. This condition has been attributed to many causes including psychiatric disturbances (e.g., restless legs is a frequent symptom of hysteria, anxiety, and depression). In periods of stress, "normal" persons are also afflicted. All of these states are associated with high central nervous system arousal. Also, restless legs syndrome was first described in England at the time when coffee and tea first were introduced in the country. Thus, diagnosis of the restless legs syndrome, as has also been observed in certain psychological disorders, may simply be the result of overdosage of ubiquitous caffeine.
Sanford Bolton, PhD and Gary Null, M.S., Journal of Orthomolecular Psychiatry
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American Psychiatric Association: First Graders' Behavior Problems Linked to Caffeinated Cola
ATLANTA, May 23, 2005--Children who are inattentive, restless, and having difficulty sleeping may be reacting to the caffeinated cola drinks in the school vending machine or the home refrigerator.
First-graders have more behavior problems on the days that they are exposed to caffeinated colas than on the days that they have caffeine-free drinks, according to Chicago investigators who reported today to the American Psychiatric Association meeting here.
The findings may provide a simple answer to some instances of children's hyperactivity, according to principal investigator Alan R. Hirsch, M.D., director of the Smell and Taste Treatment and Research Foundation and an assistant professor of both neurology and psychiatry at Rush Medical College.
"Exposure to caffeinated cola drinks impaired children's learning ability by causing restlessness, hyperactivity, and inattention," he said. "On the days that the children were drinking caffeinated drinks, their Connors scores increased an average of 5.5 points compared to the days that they were only drinking caffeine-free drinks." Dr. Hirsch is the director of the Smell and Taste. The Connors test is a standard screen for attention deficit hyperactivity disorder (ADHD).
Twenty first-grade children, 10 boys and 10 girls, participated in the study. In three-hour time segments that occurred sequentially over a two-week study period, the students consumed up to 12 ounces of either a caffeinated cola drink or a caffeine-free cola drink. The children were given 10 dimes with which they could "buy" repeat servings of their designated drink for the study session after an initial serving of two ounces. At the end of each session, the children's teacher, who did not know the purpose of the study or the type of soda each child consumed, assessed each child's behavior with a modified Connors test.
On the study days, the children consumed an average of 7.55 ounces of caffeine-free cola and 9.45 ounces of caffeinated cola (p = 0.03). On the days without caffeine, the children had an average modified Connors score of 1.55. On the days they drank caffeinated cola, the children had an average score of 7.00 (p = 0.002). Among the individual students, 60% had elevated Connors scores on the caffeine days, while 15% had higher scores on the caffeine-free days (p = 0.008). The remaining 25% had consumed the maximum servings of both types of drinks and were not included in the analysis.
After adjusting for non-caffeine related factors, such as the number of ounces consumed and the amount of sugar in the drinks, the scores were still higher on the caffeine days (p = 0.015).
"Children ages six to 11 years old conservatively drink an average of seven to eight ounces of carbonated soda per day," said Dr. Hirsch. As the findings show, "this can have a substantial impact on children's behavior in school."
"These findings are consistent with prior researchers' results," said David W. Fassler, M.D., in a comment seeking an independent perspective. "Although the sample size is small, the authors demonstrated that behavior difficulties can be caused by caffeinated beverages." Dr. Fassler is a clinical professor at the University of Vermont in Burlington, and a member of the American Psychiatric Association's board of trustees.
"The study shows why it is so important to completely evaluate young children who are having behavioral and emotional problems, and to review the child's dietary habits, including caffeinated beverages, as part of the evaluation," Dr. Fassler said. Although questions about caffeine consumption are typically part of the screen for anxiety disorders, pediatric insomnia, and ADHD, the findings are a reminder not to neglect this part of the evaluation.
Primary source: American Psychiatric Association, 158th annual meeting. Abstract #NR45.
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"Medical opposition to coffee continued into the twentieth century. A typical medical attack can be found in Morphinism and Narcomanias from Other Drugs (1902) by T. D. Crothers, M.D., superintendent of the Walnut Lodge Hospital in Connecticut, editor of the Journal of Inebriety, and professor of nervous and mental diseases at the New York School of Clinical Medicine. Dr. Crothers classed coffee addiction with morphinism and alcoholism. "In some extreme cases delusional states of a grandiose character appear; rarely violent or destructive, but usually of a reckless, unthinking variety. Associated with these are suspicions of wrong and injustice from others; also extravagant credulity and skepticism."
"A similar view of the evils of caffeine drinks can be found in A System of Medicine (1909), edited by Sir T. Clifford Allbutt, Regius Professor of Physic (Internal Medicine) in the University of Cambridge, England, and by Humphrey Davy Rolleston, M.A., M.D., F.R.C.P. The chapter on "Opium Poisoning and Other Intoxications" in this textbook, used in American as well as British medical schools, was by Sir Clifford and Dr. Walter Ernest Dixon, professor of materia medica and pharmacology, King's College, London--one of the foremost pharmacologists of his generation.
"We have seen several well-marked cases of coffee excess ... [Sir Clifford and Dr. Dixon reported]. The sufferer is tremulous, and loses his self-command; he is subject to fits of agitation and depression; he loses color and has a haggard appearance....As with other such agents, a renewed dose of the poison gives temporary relief, but at the cost of future misery."
Edward M. Brecher, Consumers Union Report on Licit and Illicit Drugs
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Following is the full text of a letter by Dan Stradford published last month on BMJ.com (formerly British Medical Journal), with commentary by psychiatrist and neurologist Stuart Shipko, M.D., founder and director of the Panic Disorder Institute:
"The failure to do full medical screenings on psychiatric patients is one of the greatest areas of neglect in modern medicine. Studies have repeatedly shown for years that psychiatric populations have more medical ailments than non-psychiatric patients. No one disputes this. And most of those same studies also show that a healthy percentage of psychiatric patients are routinely misdiagnosed with mental illness (and often placed on psychotropics for years or for life), when they, in fact, have medical problems causing or exacerbating their psychiatric symptoms. No one disputes this either.
The landmark 1980 study by Richard Hall et al ("Physical Illness Manifesting as Psychiatric Disease", Arch Gen Psychiatry, 1980, 37: 989- 995) found 46% of the psychiatric patients thoroughly examined had physical ailments causing or exacerbating their mental symptoms.
The California legislature was so shocked by this study, it ordered research, headed by Dr. Lorrin Koran of Stanford University, on how to improve the quality of medical exams in psychiatric settings. The result of that study was the "Medical Evaluation Field Manual," which sets a minimal standard for medical screenings and provides an efficient algorithm when full screenings are not practical.
The manual was distributed to all of California's counties in the late 1980s and NONE of them implemented it. A dozen years later, my nonprofit organization, Safe Harbor, has asked for and received a grant to work on getting this manual implemented.
We have posted the Field Manual on the internet at alternativementalhealth.com/articles/fieldmanual.htm.
What concerns me is that I--a layman--and a group of volunteers is having to grab the psychiatric profession by the scruff of the neck to get them to examine their own patients! This does not speak well for the profession or for its organizations, such as the American and British Psychiatric Associations....
This medical negligence cannot continue. I would like to issue a call to medical professionals to, once and for all, set and keep minimal medical screening standards for psychiatric patients so that this easily remedied medical neglect exists no more."
Response by Stuart Shipko, M.D., psychiatrist, neurologist, founder and director of the Panic Disorder Institute:
"This is so true. A long time ago when I actively practiced general medicine I was the doctor who did physical examinations on patients confined to a mental ward. I found that the labwork showed excessive abnormalities of calcium, sodium and chloride. I diligently worked up these abnormalities, but concluded that the abnormalities were due to problems in blood testing. To present this to the quality assurance committee, I reviewed the charts of the previous 50 admissions and showed the cluster of abnormalities. The response? They wanted to know what my motives were and why I cared. The fact that it was my job to care went over their heads. Medical evaluation of the 'mentally ill' is pretty much nonexistent."
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"An allergic reaction to caffeine manifests as anaphylaxis. During a state of caffeine anaphylaxis, the body enters the fight or flight mode, which may be mistaken as hyperactivity, anxiety, or panic disorder. Caffeine anaphylaxis causes cerebral vasculitis, leads to the breakdown of the blood brain barrier, and generates toxic dementia."
"Symptoms range from minimal reactions to severe psychotic states, which may include irrational behavior, disruptions in attention, lack of focus and comprehension, mood changes, lack of organizational skills, abrupt shifting of activities, delusions, hallucinations, and paranoia."
"An allergic reaction to caffeine results in poisoning of the prefrontal cortex. Damage to the underside area on the prefrontal cortex, above the eye sockets, generally renders a person absent minded and interferes with the ability to monitor personal activities (Carter, 1998). Injury results in loss of verbal and social inhibition...."
"While others may notice menacing changes in behavior or personality changes, the victim may not."
Ruth Whalen, MLT, in "Caffeine-Induced Anaphylaxis: A Progressive Toxic Dementia"
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"A cola-induced psychosis has been reported....Caffeine-induced psychoses ranged from increased agitation and insomnia to frank psychosis."
"The treatment for caffeine-induced psychosis is to withhold further caffeine."
Clinical Management of Poisoning and Drug Overdose, 3rd Edition (1998) [Link]
Michael W. Shannon, MD, MPH, Director, Lead and Toxicology Clinic, The Children's Hospital Boston; Professor of Pediatrics, Harvard Medical School
Lester M. Haddad, MD, Clinical Professor in Family Medicine, Medical University of South Carolina; Attending Emergency Physician, Bon Secours St. Francis Xavier Hospital
James F. Winchester, MD, Professor of Medicine, Division of Nephrology, Department of Medicine, Georgetown University Medical Center
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"Thus we come to the coffee paradox--the question of how a drug so fraught with potential hazard can be consumed in the United States at the rate of more than a hundred billion doses a year without doing intolerable damage--and without arousing the kind of hostility, legal repression, and antisocial condemnation aroused by the illicit drugs.
"The answer is quite simple. Coffee, tea, cocoa, and the cola drinks have been domesticated. Caffeine has been incorporated into our way of life in a manner that minimizes (though it does not altogether eliminate) the hazards inherent in caffeine use."
Edward M. Brecher, Consumers Union Report on Licit and Illicit Drugs
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"People who drink too much coffee are at risk of caffeine psychosis, according to a new report. It found that too much caffeine can lead to marked changes in personality and make drinkers more aggressive, anxious and temperamental."
Roger Dobson, The Independent, London
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"The 4 caffeine-induced psychiatric disorders include caffeine intoxication, caffeine-induced anxiety disorder, caffeine-induced sleep disorder, and caffeine-related disorder not otherwise specified (NOS)."
Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM-IV)
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"Although infrequently diagnosed, caffeinism is thought to afflict as many as one person in ten of the population."
JE James and KP Stirling, "Caffeine: A Summary of Some of the Known and Suspected Deleterious Habits of Habitual Use,"British Journal of Addiction, 1983;78:251-58.
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"Thousands are in mental institutions today because of no greater matter than that of the use of caffeine. Psychiatrists are now publishing articles indicating that there are numerous cases of depression and anxiety in mental institutions who need no other treatment than to be taken off caffeine. It would seem that with such a simple remedy available, many thousands of people could be returned to their full usefulness promptly.
"However, the use of caffeine is so traditional and firmly entrenched that it is almost impossible to remove caffeinated drinks from the diet of patients in the mental institutions. Soft drink machines, coffee dispensers, and the traditional coffee break are common pastimes in mental institutions, and with those who are mentally ill at home."
Calvin Thrash, M.D., Author, Food Allergies Made Simple
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"[When caffeine is taken in excess], anxiety-related symptoms become increasingly apparent. A case of caffeinism, which presented as a paranoid delusion, is reported as an extreme example of this. A study of 60 hospital inpatients revealed that about 40% of them consumed sufficient caffeine to produce symptoms of caffeinism. It is thus recommended that all patients should be questioned on their caffeine intake. Also, caffeinism should be considered as a differential diagnosis of anxiety states."
DC Mackay and JW Rollins, "Caffeine and caffeinism,"Journal of the Royal Naval Medical Service,1989;75(2):65-7.
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"Recently published studies and reports of personal observations have shown without doubt that caffeine abuse (caffeinism) may result in a syndrome which resembles and may be confused or confounded with true psychotic states. This may lead to misdiagnosis and mistreatment. A question arises from the varied reports of caffeine consumption in psychiatric populations: Does caffeine stimulate psychosis or does psychosis stimulate caffeine consumption?"
Sanford Bolton, PhD and Gary Null, M.S., Journal of Orthomolecular Psychiatry
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"The existence of a caffeine dependence syndrome, which includes evidence of continued caffeine consumption depite medical or psychological problems from caffeine consumption and unsuccessful efforts to quit caffeine use, provides a further similarity between caffeine and classic drugs of dependence."
EC Strain, GK Mumford, K Silverman et al., "Caffeine Dependence Syndrome: Evidence from case histories and experimental evaluations."Journal of the American Medical Association, 1995;273:1418-19.
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"A longitudinal case report shows a sudden remission of the severe course of a seasonal bipolar disorder after 10 years of psychopharmacological treatments. The discontinuation of heavy caffeine intake appears to have contributed to the outcome."
Abstract of: L Tondo and N Rudas, "The course of a seasonal bipolar disorder influenced by caffeine," Journal of Affective Disorders, 1991;22 (4):249-251
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Psychiatrists' initial verdict on one caffeine-poisoned patient, in a case cited by Dr. Edward M. Brecher in the landmark "Consumers Union Report on Licit and Illicit Drugs":
"Hysteria without question. When she failed to improve and remained wildly manic for several days, she was transferred to a psychiatric hospital, where she was at first kept tied to a bed. After almost two months in the hospital, during which she slowly recovered, a mild relapse occurred. Investigation showed that she was drinking coffee, four cups a day. At this point, suspicion for the first time turned to caffeine. Coffee and tea were removed from her vicinity and soon she again became entirely normal, and was dismissed from the hospital. (MC McManamy and PG Schube, "Caffeine Intoxication: Report of a Case the Symptoms of which Amounted to a Psychosis," New England Journal of Medicine, 1936;215:616-620.)
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"Caffeine toxicity may be mistaken for bipolar disorder. Symptoms include: chattiness, repetitive thought and action (resembling obsessive compulsive disorder), restlessness, psychomotor agitation, alternating moods, anger, impulsiveness, aggression, omnipotence, delirium, buying sprees, lack of sexual inhibition, and loss of values."
"Toxicity is known to cause excitement, agitation, restlessness, shifting states of consciousness, and toxic psychosis, mimicking amphetamine psychosis. Allergic individuals may be erroneously diagnosed, medicated, and lost in a dark disturbed world, until death."
Ruth Whalen, MLT, "How Much Mental Illness Is an Allergy to Caffeine?"
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"Jittery? Peevish? Not Sleeping? What Are You Drinking?"
by Richard A. Friedman, M.D.
The patient was led reluctantly into my office by his girlfriend.
Over the course of the past month, she explained, Adam had become uncharacteristically nervous and snappy. He hardly slept, and when he did she noticed that his muscles twitched.
Adam’s own account did not differ from his girlfriend’s. He was a graduate student and he needed to study for his qualifying exams, he said, explaining his irritability.
I noticed during the consultation that Adam was sweaty and nervous and that the muscles around his eyes twitched. He had already seen his internist, who told him that his physical exam and routine lab tests were entirely normal. This is nothing more than stress, his doctor announced.
In my office, Adam’s resting heart rate was 110, which is on the fast side for a fit 31-year-old man. His blood pressure was mildly elevated at 140/80, but just talking to a psychiatrist can be nerve-racking for many people.
After a review of his psychiatric history, which was entirely negative, I asked him whether he was using any recreational drugs. Aside from experimenting with marijuana as a teenager, he said he had not done so. I never stop at the first denial, so I inquired about specific drugs like cocaine and amphetamines, which are well known to cause anxiety states.
“No way,” he said, and I believed him.
Maybe this was just plain old-fashioned anxiety. After all, Adam was facing enormous academic pressure in a prestigious institution, and he felt that his future was riding on the outcome of an exam. So I gave him some reasonable advice about dealing with stress, and sent him on his way with a clean psychiatric bill of health.
Two weeks later, I got a call from Adam’s girlfriend saying that he was worse than ever. When I saw him, he looked haggard and anxious, and I was convinced that I had missed something important the first time around. Did he have an undiagnosed medical disease? Covert substance abuse? Exposure to an environmental toxin?
In painstaking detail, we reviewed his medical and psychiatric history, but nothing stood out. Exasperated, I asked him to tell me what he did from the moment he got out of bed until he went to sleep: activities, diet, everything. Then I got it.
After the habitual two cups of Starbucks coffee, Adam set to work. So far so good. But as the academic pressure mounted he had to work longer hours, and that meant more coffee--a lot more coffee than he had ever consumed in his life. In fact for six weeks he had been drinking up to 10 cups of coffee daily.
That is a lot caffeine considering that each large cup contains on average of about 375 milligrams, according to a 2003 study of caffeinated coffee published in The Journal of Analytical Toxicology. With 10 cups a day Adam was turbocharged with nearly 4 grams of caffeine.
So Adam was not just nervous about his academic work; he was suffering from caffeine intoxication.
How, you might wonder, could such a ubiquitous substance be toxic? With an average of one to three cups of coffee a day, most people get 100 to 300 milligrams of caffeine. With chronic exposure, though, people become accustomed to the stimulant effects of caffeine. In contrast, a sudden increase in caffeine consumption can easily produce caffeine intoxication.
In general more than 1.5 grams of caffeine a day can cause the typical symptoms of caffeinism: anxiety, insomnia, irritability and palpitations.
Caffeine is far and away the most widely used stimulant in the world. It is actually a member of a class of compounds called xanthines that includes theobromine, which is abundant in chocolate, and theophylline, the major xanthine in tea.
Caffeine works by blocking the calming and analgesic effects of the neurotransmitter adenosine in the brain. In moderate doses, caffeine enhances arousal and performance. At higher doses, caffeine blocks a majority of adenosine receptors and can produce anxiety and hypersensitivity to pain.
Of course Adam’s response to caffeine was an extreme example. But the effects of this popular stimulant encompass a broad spectrum, from the pleasant activation of morning coffee to the extreme agitation and anxiety of caffeine intoxication.
Judging from the sheer number of consumer products spiked with caffeine, one would think we were a nation of narcoleptics, desperately trying to stay awake. From “enhanced” water to sports drinks to dietary supplements, caffeine is a common additive. And as the food and supplement industries search for new stimulants following the recent ban on ephedra, it would hardly be surprising to find caffeine use on the rise.
After all, the hectic pace of our modern life practically demands that we switch ourselves on and off. Sure, we can stave off fatigue with caffeine, but sometimes nature pays us back richly with anxiety and sleeplessness if we are lucky, or caffeine intoxication if we indulge in excess.
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While the FDA labels caffeine as GRAS ("Generally Regarded As Safe"), chemical manufacturers label it "potentially fatal if inhaled, swallowed or absorbed through the skin."
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"There is no doubt that the excitation of the central nervous system produced by large amounts of caffeine is followed by depression."
J. Murdoch Ritchie in The Pharmacological Basis of Therapeutics, Goodman and Gilman eds.
