Drug Dependence and Antidepressants

Question 1

How do cocaine and methamphetamine differ?

Answer 1

In their selectivity for receptors in the CNS and their affinity

Question 2

What do the cortical areas/circuits involved in drug abuse and addiction control?

Answer 2

Motivation/drive
Memory/learning
Reward/salience
Inhibitory control

Question 3

What is the biochemical effect of drugs of dependence?

Answer 3

Increase dopamine in the nucleus accumbens

Question 4

What effect does amphetamine have in the CNS?

Answer 4

Releases DA, 5HT and NA

Question 5

What is the mechanism of dependence in amphetamine use?

Answer 5

Dopaminergic actions in nucleus accumbens

Question 6

What effect does MDMA have in the CNS?

Answer 6

Releases DA and 5HT

Question 7

What physiological effect of MDMA is of most concern in terms of its potential to cause fatalities?

Answer 7

Disrupted thermoregulation (causing chills and sweating, can lead to dehydration and death)

Question 8

What is the characteristic effect of LSD use?

Answer 8

Confusion of sensory modalities leading to visual, auditory and tactile hallucinations

Question 9

For which drugs of dependence does tolerance occur?

Answer 9

LSD

Question 10

Where does LSD act and what kind of activity does it have?

Answer 10

Agonist at 5HT-2 autoreceptors on neurones in raphe nuclei

Question 11

To what drug class does caffeine belong?

Answer 11

Methylxanthine

Question 12

List the 2 pharmacological actions of caffeine

Answer 12

Adenosine antagonist

PDE inhibitor

Question 13

List 3 actions of ethanol on the CNS

Answer 13

Inhibits Ca2+ channel opening
Enhances GABA action via GABA-A receptors
Inhibits glutamate receptors (NMDA-type channel)

Question 14

What is the effect of flumazenil?

Answer 14

Blocks the action of ethanol on GABA-A receptors

Question 15

List 5 neurological signs of ethanol dependence

Answer 15

Tremor
Agitation
Hyperactive reflexes
Convulsions
Delirium

Question 16

List 5 physical signs of ethanol dependence

Answer 16

Anorexia
Vomiting
Postural hypotension
Sweating
Hyperpyrexia (extremely high fever)

Question 17

What class of receptors are cannabinoid receptors?

Answer 17

GPCRs

Question 18

What is the name of the endogenous chemical that activates cannibinoid receptors?

Answer 18

Anandamide

Question 19

List 4 peripheral effects of THC

Answer 19

Tachycardia
Vasodilation
Reduced intraocular pressure
Bronchodilation

Question 20

List 2 1st generation classes of antidepressants

Answer 20

TCAs

MAOIs

Question 21

List 2 2nd generation classes of antidepressants

Answer 21

SSRIs

SSNRIs

Question 22

List 2 3rd generation classes of antidepressants

Answer 22

Novel monoaminergic drugs

Non-monoaminergic drugs

Question 23

List 3 pharmacological actions of TCAs

Answer 23

Inhibit neuronal uptake of NA and 5HT
Antagonise a-adrenoceptors, muscarinic receptors, histamine receptors and 5HT receptors
Quinidine-like membrane stabilising action at very high concentrations

Question 24

List 4 drawbacks of using TCAs

Answer 24

Poor selectivity
Clinical effect takes weeks to develop
Narrow therapeutic window
Long(ish) half life meaning gradual accumulation may occur, causing slowly developing side effects

Question 25

What effect do MAOIs have on the CNS?

Answer 25

Increase levels of 5HT, NA and DA

Question 26

List 2 irreversible MAOIs

Answer 26

Phenelzine

Tranylcypromine

Question 27

What is the “cheese reaction”?

Answer 27

Interaction between irreversible MAOIs and tyramine (in many foods including cheese, red wine, chocolate, bananas) causing hypertensive crisis

Question 28

Name a reversible MAOI. What MAO subtype is it selective for?

Answer 28

Moclobemide, selective MAO A

Question 29

List 4 side effects of reversible MAOIs

Answer 29

Postural hypotension
Dizziness
Nausea
Insomnia