Chapter 8 Flashcards
What is the world’s most popular drug?
Caffine
Where are Caffeine and other methylxanthine alkaloids from?
occur naturally in over 60 plant species.
How long have humans used caffeine?
Humans have used it in beverages since ancient times—possibly dating back to the Stone Age
How many people in the world use caffeine and how much?
The estimates we do have shows caffeine in some form
is used regularly by 90% of the world’s population with an average of about 70 mg per capita per day (The US is around 170 mg per day)
What is caffeine’s method of action?
The blocking of adenosine receptor sites. Adenosine is a major inhibitory transmitter. (The antagonism of adenosine receptors)
What are the processes blocked by caffeine?
Behavioral sedation, regulation of oxygen delivery to cells, dilation of cerebral and coronary blood vessels
What is the absorption of caffeine?
rapidly absorbed from the gastrointestinal
tract and distributed throughout the body. Quickly reaches the brain because it passes the blood brain barrier easily
What are the peak levels of caffeine?
15 to 45 minutes after ingestion (but can depend on the source)
What is the half-life in blood of caffeine?
from three to seven hours (varies widely among people)
What is the distribution of caffeine throughout the body?
equally throughout the body’s water and passes through the placenta
Where does the metabolization of caffeine happen?
primarily in the liver
Where is the excretion of caffeine?
almost entirely in the urine with
less than 10% in pure form
Caffeine is unique in that it has the reverse picture of withdrawal and tolerance than most drugs:
it induces dependence without tolerance
What is the most common withdrawal symptoms of caffeine?
Headache and fatigue
What are the symptoms of caffeine abstinence?
Depression, Decreased alertness, Less contentment and relaxed mood, Decreased activity and energy, Greater sleepiness and drowsiness, Increased irritability
What is the tolerance of caffeine?
develops to renal function, sleep, blood pressure, and heart rate. However, little tolerance develops to caffeine’s stimulant and behavioral effects
What are the acute (short term) effects of caffeine?
diuresis (the need to pee) , heart stimulation, relaxation of smooth muscles, and gastric acid stimulation
What are the behavioral and performance effects of caffeine?
Mood: CNS-stimulation action of caffeine elevates mood
• Feeling associated with moderate doses of caffeine: energized, creative, efficient, confident, alert
• Performance: range of caffeine effects is wide; impairs decision-making part of a task but improves the motor component
What are the world’s three most popular drugs?
Caffeine, nicotine, and alcohol
What are the interactions of alcohol and caffeine?
key findings show mixing them reduced the perception of physiological changes, but not the actual changes, and did not reduce alcohol effects on motor coordination and reaction time
What are the acute toxic effects of caffeine?
Lightheadedness, tremulousness, breathlessness,
headache, and irregular heartbeat
What happens if you reach above 1000 mg of caffeine daily?
muscle twitching, rambling flow of thought and speech, cardiac arrhythmia, psychomotor agitation, also possibly ringing in the ears and seeing flashes of light
What is a lethal dose of caffeine?
10 g for adults (about 75 cups of coffee), 100 mg/kg for children
What are the chronic effects of caffeine use?
Moderate symptoms like indigestion, tremors, palpitations, and insomnia may be linked (but at higher doses). No other associations on long-term health effects. No effects on reproduction have been found.
What are the potential health benefits of caffeine?
frequent coffee drinkers have
a lower risk of dying from a variety of diseases:
diabetes, heart disease, respiratory disease, stroke,
and infections
What are the therapeutic uses for caffeine?
Caffeine: It is a part of the treatment for many illnesses.
• Other methylxanthines also have therapeutic value.
• Example: caffeine is used in cold remedies to counteract depressive side effects of primary medications.
