What is caffeine?
A: Caffeine is a central nervous system stimulant of the methylxanthine
class.
What is it used for?
A: As a cognitive enhancer, increasing alertness and attentional
performance.
Caffeine acts by blocking binding of adenosine to the
adenosine A1 receptor, which enhances what?
A: The release of the neurotransmitter acetylcholine.
Caffeine also increases cyclic AMP levels through what?
A: Nonselective inhibition of phosphodiesterase.
Caffeine is a bitter, white crystalline purine, a
methylxanthine alkaloid, and is chemically related to what?
A: The adenine and guanine bases of deoxyribonucleic acid (DNA) and
ribonucleic acid (RNA).
Where is it found?
A: In the seeds, fruits, nuts, or leaves of a number of plants native to
Africa, East Asia and South America.
It helps them protect against what?
A: Herbivores and from competition by preventing the germination of nearby
seeds, as well as encouraging consumption by select
animals such as
honeybees.
What is the best-known source of caffeine?
A: The coffee bean, the seed of the Coffea plant.
Why may people drink beverages containing caffeine?
A: To relieve or prevent drowsiness and to improve cognitive performance.
To make these drinks, caffeine is extracted by what
process?
A: Steeping the plant product in water, a process called infusion.
What are some Caffeine-containing drinks?
A: Coffee, tea, and cola, are consumed globally in high volumes.
In 2020 how many coffee beans were consumed globally?
A: Almost 10 million tons.
Caffeine is the world's most widely consumed what?
A: Psychoactive drug.
Unlike most other psychoactive substances, caffeine
remains largely what?
A: Unregulated and legal in nearly all parts of the world.
Caffeine is also an outlier as its use is seen as what?
A: Socially acceptable in most cultures and even encouraged in others,
particularly in the Western world.
Caffeine can have both positive and negative what?
A: Health effects.
It can treat and prevent premature infant what?
A: Breathing disorders bronchopulmonary dysplasia of prematurity and apnea
of prematurity.
Caffeine citrate is on the WHO Model List of what?
A: Essential Medicines.
It may confer a modest protective effect against what?
A: Some diseases, including Parkinson's disease.
Evidence of a risk during pregnancy is equivocal; some
authorities recommend that pregnant women limit caffeine to the equivalent
of how much?
A: Two cups of coffee per day or less.
Caffeine can produce a mild form of what?
A: Drug dependence associated with withdrawal symptoms such as sleepiness,
headache, and irritability when an individual stops using caffeine.
Tolerance to the autonomic effects of increased blood
pressure and heart rate, and increased urine output, develops with what?
A: Chronic use.
Toxic doses, over 10 grams per day for an adult, are
much higher than what?
A: The typical dose of under 500 milligrams per day.
A cup of coffee contains how much caffeine?
A: 80–175 mg.
Pure powdered caffeine, which is available as a dietary
supplement, can be lethal in what dose?
A: Tablespoon-sized amounts.
Some people use caffeine-containing beverages such as
coffee or tea to try to treat their what?
A: Asthma.
It appears that caffeine in low doses improves what?
A: Airway function in people with asthma.
The addition of caffeine (100–130 mg) to commonly
prescribed pain relievers such as paracetamol or ibuprofen modestly improves
what?
A: The proportion of people who achieve pain relief.
Consumption of caffeine after abdominal surgery
shortens what?
A: The time to recovery of normal bowel function and shortens length of
hospital stay.
Caffeine was formerly used as a second-line treatment
for what?
A: ADHD.