CNS stimulants

Question 1

Caffeine is a _______, which is structurally similar to purines.

Answer 1

methylxanthine

Question 2

What are two methylxanthine related molecules found in tea?

Answer 2

theophylline

theobromine

Question 3

What is the mechanism of caffeine?

at normal dose

Answer 3

competitive agonist of adenosine receptors
=> postsynaptic receptors produce IPSP
=> presynaptic receptors inhibit glutamate
*dis-inhibition leading to CNS stimulation

Question 4

What is the mechanism of caffeine at higher doses?

Answer 4

inhibit cAMP phosphodiesterase
=> increase in cAMP
beneficial effects in asthma

also induces release of Ca++ from intracellular ER

=>stimulate medullary respiratory and CV centers (tachycardia)

Question 5

Cocaine is active in the _____ form, predominant in ____ pH.

Answer 5

unionized/unprotonated form (B)

predominates in high pH

Question 6

Cocaine has a _____ half-life of about ___ minutes.

Answer 6

Short half-life about 50 minutes.

in CNS even shorter about 10-30 minutes.

Question 7

What is the mechanism of cocaine?

Answer 7

inhibitor of reuptake of NE, dopamine, serotonin

Question 8

Reinforcing effects of cocaine are due to ____ in the synapse.

Answer 8

Dopamine

Question 9

Increase in NE due to cocaine can cause what peripherally and centrally?

Answer 9

peripheral sympathomimetic - vasoconstrict, tachycardic

centrally cause alertness, vigilance

Question 10

Fetal effects of cocaine? (3)

Answer 10

low birth weight
learning and emotional problems
attachment disorder

Question 11

Cocaine is often used as local anesthetic in the _______.

Answer 11

upper respiratory tract (surgery of the nose)

anesthetic & vasoconstrict!

Question 12

Amphetamine and methamphetamine are structurally similar to _____.

Answer 12

norepinephrine

Question 13

Unlike cocaine, amphetamine and methamphetamine are well absorbed ______ and has _____ half-life.

Answer 13

orally, longer

Question 14

What are the mechanisms of action for amphetamine and methamphetamine? (4)

Answer 14

-release NE, DA, 5HT from neurons
-block reuptake
-partial agonist of alpha receptors
-MAO inhibitor at high doses
(more NE-life effect than cocaine)

Question 15

What are some clinical uses for amphetamine and methylphenidate? (2)

Answer 15

• narcolepsy

- ADHD

Question 16

What are the side effects of amphetamine and methylphenidate (6)

Answer 16

• insomnia
• abdominal pain
• anorexia, weight loss
• suppression of growth
• fever
• facial ticks

Question 17

What are the toxicities of amphetamine and methylphenidate? (5)

Answer 17

sympathomimetic
psychosis
neurotoxic
meth mouth
abuse

Question 18

Why is methamphetamine more liable to abuse?

Answer 18

gets into brain better!

Question 19

Nicotine affects autonomic ganglia and causes (sympathetic & parasympathetic)

Answer 19

• sympathetic: release of epinephrine from adrenal

- parasympathetic: GI effects (nausea, increased motility)

Question 20

Nicotine produces neuronal excitation through _____ ______.

Answer 20

membrane depolarization

Question 21

Nicotine activates dopamine signaling in _____ ______ in the CNS; making it reinforcing.

Answer 21

nucleus accumbens

Question 22

What “zone” does nicotine activate and cause nausea?

Answer 22

chemoreceptor trigger zone

Question 23

Describe in ONE word why the first cigarette of the day is the best.

Answer 23

tachyphylaxis

Question 24

Nicotine withdrawal symptoms include (5)

Answer 24

• irritability, hostility, impatience
• anxiety
• depression
• difficulty concentrating
• increased appetite, weight gain

Question 25

Name two pharmacotherapies for nicotine dependence

Answer 25

bupropion, varenicline

Question 26

How does bupropion work?

Answer 26

reduces craving and lessen withdrawal symptoms

-antidepressant

Question 27

How does varenicline work?

Answer 27

partial agonist of nicotinic receptors

-blocks effects of nicotine (since it’s partial)

Question 28

What is the major concern with varenicline?

Answer 28

increased suicidal thoughts and depression!