Caffeine

Question 1

Caffeine

Answer 1

• Mild psychostimulant of the xanthine family
• Found in certain plants
• The most widely used drug internationally

Question 2

Which plants are xanthines found in?

Answer 2

• Kola nuts
• Cocoa tree nuts
• Tea leaves
• Coffee beans

Question 3

Energy drinks (8oz) contain around ____mg of caffeine

Answer 3

75mg

Question 4

A 10 oz cup of coffee contains approx. [answer] mg of caffeine, a 10 oz cup of tea contains approximately [answer] mg of caffeine.

Answer 4

10 oz cup of coffee: 200 mg
10 oz cup of tea: 100 mg

Question 5

Brewed coffee became popular around:

Answer 5

1000 C.E.

Question 6

Who identified caffeine’s chemical properties?

Answer 6

Emil Fischer

Question 7

Caffeine products are administered [answer]

Answer 7

Orally

Question 8

100% of caffeine is absorbed across ____

Answer 8

Intestinal walls

Question 9

The acids that caffeine contain are called

Answer 9

Cholorogenic acids

Question 10

Caffeine is metabolized in the ____

Answer 10

Liver

Question 11

CYP-1A2

Answer 11

The main caffeine-metabolizing enzyme

Question 12

CYP-2E1

Answer 12

A caffeine-metabolizing enzyme (secondary to CYP-1A2)

Question 13

What are two types of substances that affect the metabolization of caffeine?

Answer 13

Antidepressants: Are CYP-1A2 (caffeine metabolizing enzyme) inhibitors, reducing the metabolization of caffeine
Smoking (not the nicotine itself): Enhances CYP-1A2, increases the metabolism of caffeine

Question 14

The metabolism of caffeine produces these active metabolites:

Answer 14

Theophylline, theobromine, and paraxanthine (the latter of which occurs only when metabolically converted from caffeine).

Question 15

The body primarily eliminates caffeine through the

Answer 15

Kidneys

Question 16

The rate of elimination of caffeine varies widely, from approximately [answer] to [answer] hours.

Answer 16

Three to ten hours

Depends on the individual. Smoking cigars or cigarettes doubles the rate of caffeine elimination.

Question 17

Caffeine’s primary mechanism of action

Answer 17

Antagonism of adenosine A1 and A2 receptors

Question 18

Adenosine

Answer 18

A neuromodulator that has inhibitory effects on neurons throughout the central and peripheral nervous system. Adenosine specifically has inhibitory effects on cholinergic neurons in the cerebral cortex, and on dopamine neurons in the basal ganglia.

Question 19

Physiological, behavioural and subjective effects of caffeine

List some of these effects

Answer 19

Increased heart rate, blood vessel constriction, increased breathing rate, reduced appetite, increased attention, alertness and positive mood

Question 20

Tolerance for caffeine can occur with many of its [answer] effects, but may not occur with its [answer] effects.

Answer 20

Tolerance for caffeine can occur with many of its subjective effects, but may not occur with its physiological effects.

Question 21

Can excessive daily caffeine intake cause withdrawal when the person stops consuming caffeine?

Answer 21

Yes. This is called caffeine withdrawal and can cause headaches, fatigue, irritability and low mood.

Question 22

Is caffeine addictive?

Answer 22

This is controversial, but caffeine is not usually considered addictive, considering “that caffeine appears neither irresistible nor a cause of social disruption” (Satel, 2006).