Caffeine

Caffeine is a central nervous system (CNS) stimulant. It is in the methylxanthine class. It is found in many plants, and is used in drinks like coffee, some teas, some soft drinks, and energy drinks. It can be harmful for both humans and animals if a large amount is consumed. If a person ate 10-13 grams of caffeine quickly, between 80 and 100 cups of coffee, they would overdose and may die. It is the world's most popular psychoactive drug, and is legal in nearly all of the world.
Sources
Caffeine is the main drug that is in coffee. Coffee comes from a tree. The seeds of the tree are roasted to make coffee.
Caffeine comes from other plants as well. It is in guarana, yerba mate, cacao, and some plants used to make tea. The plants use caffeine as a pesticide. This is a chemical that kills insects if they eat the plant. It is the way the plant protects itself.
Caffeine was first extracted from cocoa beans into its purest form which is a white powder and the word originated from the German word "kaffee" and the French word "cafe" which both mean caffeine.
It is called guaranine when it comes from the guarana plant and theine when it comes from a tea plant. It is called mateine in the mate drink. This drink is an infusion made with Yerba mate.
What caffeine is
Caffeine is a stimulant drug. A stimulant is a drug that increases body actions like heart rate, blood pressure, and metabolism. It makes a person more awake and alert.
Caffeine also is a diuretic. This means it makes a person make more urine (the waste liquid a person makes).
The caffeine chemical is called a xanthine alkaloid. This is a group of chemicals that are stimulants. Some xanthine alkaloids (like theophylline) are used to help asthma.
What caffeine is used for
The biggest use of caffeine is as a stimulant. People drink coffee and other drinks with caffeine to stay awake.
Doctors sometimes use caffeine as a medicine. It is used for headaches (head pain). It is sometimes used to help premature (born very early) babies to breathe. The short-term risk of this treatment seems to be that the babies treated gain less weight than usual.
Caffeine is sometimes given to people after a lumbar puncture. This is a test to see if someone has meningitis.
In the beginning caffeine was found to relieve hunger, so it was used for weight loss. That did not last because people were using too much. Caffeine can be a very dangerous drug when not used in the right way.
Caffeine also has medicinal properties. It is used in many over the counter medicines, such as Excedrin, Midol and Anacin. When combined with other analgesics, caffeine can help to alleviate headaches and cramps.
Problems with caffeine
The largest problem with caffeine is addiction. This is when people get bad symptoms when they do not have the drug. When people have withdrawal (feel bad because they do not have the drug) they drink more. This makes them feel better. But if they cannot get more, they are likely to feel some of the symptoms listed below:
Headaches
Being tired or need to sleep
Caffeine inhibits sleep and in the long-term alters brain functions
Sleep deprivation leads to a weakened connectivity between the amygdala and medial prefrontal cortex which regulate mood and emotion.
This causes the consumer to feel irritable, tired, restlessness, and anxious.
Nausea (feeling like vomiting)
Caffeine can also hurt people if they drink a lot at once. If someone takes too much of a drug at once it is called an overdose. Caffeine overdose is a medical diagnosis. It is called: Caffeine-Induced Organic Mental Disorder or Caffeine Intoxication. People with this can have these symptoms:
Very bad feelings like:
Paranoia (feeling as if people are about to hurt the person)
Restlessness or nervousness (with the person feeling like he cannot sit down or rest)
Anxiety (very bad worry)
Muscle movements that cannot be stopped
Very fast heart rate
Abnormal heart rhythms (even heart stopping)
Very high blood pressure
Vomiting
Confusion (not knowing who the person is or where he/she is)
Caffeine helps for
Caffeine also has some strong advantages:
Lower risk of coronary disease
Cut stroke risk
Speed up metabolism
Increases memory
Helps ward off Alzheimer's
Reduces kidney stone risk
How much caffeine is safe
250-300 mg of caffeine a day is a moderate amount. That is as much caffeine that is in three cups of coffee (8oz each cup). More than 750-1000 mg a day is a significant amount, but is very unlikely to kill someone. The Lethal Dose 50 of caffeine is 192 mg per kilogram, in rats. In humans, it is between 150 and 200 mg per kilogram (70-90 per pound.)
Caffeine is in many drinks and foods. This is approximate amounts of caffeine in some food and drink:
Brewed coffee - 40 to 220 mg in a cup
Instant coffee - 30 to 120 mg in a cup
Decaffeinated coffee (with most caffeine taken out) - 3 to 5 mg in a cup
Tea - 20 to 110 mg in a cup
Soda drinks with caffeine - 36 to 90 mg in 12 ounces. Some people think that soft drinks which are light in color do not contain caffeine. This is not always true.
Milk chocolate - 3 to 6 mg in an ounce
Bittersweet chocolate - 25 mg in an ounce
One ounce - abbreviated oz - is 30 ml.
A 'cup' is 8 oz (240 ml.)
Different ways to get 200mg of caffeine
References
Other websites
Scientific information
eMedicine Caffeine-Related Psychiatric Disorders
The Consumers Union Report on Licit and Illicit Drugs, Caffeine-Part 1 Part 2
The Physician and Sportsmedicine: Caffeine: A User's Guide
Caffeine: Psychological Effects, Use & Abuse
Caffeine Withdrawal Recognized as a Disorder
Is Caffeine a Health Hazard?
Others
Caffeine Withdrawal Symptoms
Caffeine: How Stuff Works
Caffeine: The most popular psychoactive drug, Broke but Shredded, January 2022
Erowid Caffeine Vaults
#caffeine! - The Caffeine Information Archive
Naked Scientists Online: Why do plants make caffeine?
Alcohol and Drugs History Society: Caffeine news page
Coffee: A Little Really Does Go a Long Way, NPR, September 28, 2006
Does coffee really give you a buzz? by John Triggs in the Daily Express April 17 2007
Burgower, Rachael. "The Effects of Energy Drinks on Sleep and Daily Functioning." , 2014, pp. 1-59.
News
National Post: Caffeine linked to psychiatric disorders
Organonitrogen compounds
Psychoactive drugs
Former good articles