Lesson B6 - Pharmacology

Question 1

The psychoses are among the most severe psychiatric disorders. People with this disorder suffer
from a

Answer 1

marked impairment of behaviour.

Question 2

There are at least two subdivisions of psychosis

Answer 2

: (a) organic, and (b) functional (of unknown cause)

Question 3

Organic psychoses are associated with

Answer 3

causes that are understood and definable e.g. toxic,

metabolic or neuropathological changes. T

Question 4

Functional (of unknown cause) psychoses are characterized by

Answer 4

retention of orientation and
memory in the presence of severely disordered thought or reasoning, emotion and behaviour.
The functional psychoses include schizophrenia

Question 5

Affective disorders are characterized primarily by a

Answer 5

change in emotion or mood

Question 6

Affective disorders consist mainly of a single

disorder of mood - either mania or

Answer 6

severe depression

Question 7

Mania is characterized by elation,

hyperactivity, and uncontrollable thought and speech. An individual suffering from

Answer 7

m depression

has feelings of intense sadness and self-disapproval, and physical and mental slowing.

Question 8

An individual suffering from manic-depressive disorder exhibits

Answer 8

alternating periods of mania

and depression.

Question 9

In contrast to the psychoses, individuals suffering from neuroses retain the ability to

Answer 9

comprehend reality

Question 10

Neuroses - . The symptoms may involve mood
changes such as anxiety, panic or restlessness, and a feeling of being ill at ease. Individuals may
exhibit limited

Answer 10

abnormalities of thought such as obsessions or irrational fears or of behaviour
such as rituals or compulsions.

Question 11

Symptoms of

schizophrenia are classified as

Answer 11

positive and negative.

Question 12

The positive symptoms include delusions

and hallucinations, bizarre behaviour, lack of logic and incoherence while

Answer 12

apathy, social

withdrawal and loss of motivation are among the symptoms referred to as negative symptoms.

Question 13

The theory of schizophrenia – the dopamine hypothesis is the most fully developed theory of
schizophrenia, but recent evidence indicates

Answer 13

that other neurotransmitters such as serotonin,

gamma-aminobutyric acid, and glutamic acid may be involved in schizophrenia.

Question 14

schizophrenia =

Answer 14

excessive dopaminergic activity

Question 15

Two other transmitters have also been postulated to play a role in schizophrenia

Answer 15

serotonin and glutamate.

Question 16

Most of the “typical” antipsychotic drugs are

Answer 16

potent blockers of postsynaptic dopamine

receptors in the CNS

Question 17

Drugs that increase dopaminergic activity such as levodopa (a precursor of dopamine),
amphetamines (releasers of dopamine), or apomorphine (a direct dopamine receptor
agonist) either

Answer 17

aggravate schizophrenia or induce it in some individuals.

Question 18

Using a technique known as positron emission tomography (PET), dopamine receptor
density has been shown to be

Answer 18

higher in schizophrenic than in non-schizophrenic persons.

Question 19

Antipsychotic action can be explained by antagonism of dopamine receptors in the

Answer 19

mesolimbic and mesofrontal systems of the brain (meso = middle)

Question 20

Extrapyramidal movement disorders: Antagonism of dopamine receptors in the

Answer 20

nigrostriatal system.

Question 21

Extrapyramidal movement disorders: Endocrine effects: Dopamine in the hypothalamus exerts a tonic inhibitory effect on prolactin
release from

Answer 21

m the pituitary gland

Question 22

Blockade of histamine receptors:

Adverse effects:

Answer 22

Sedation, drowsiness, and weight gain

Question 23

Blockade of α-adrenoceptors:

Adverse effects:

Answer 23

Postural hypotension (hypotension when assuming an erect position), 
dizziness, reflex tachycardia

Question 24

Clozapine is a very useful addition to our therapeutic armamentarium of antipsychotic drugs
because it relieves both the positive and negative symptoms of schizophrenia. Since patients
have fewer

Answer 24

extrapyramidal side effects when taking clozapine, compliance is better with
clozapine than with older antipsychotics

Question 25

Clozapine can cause

Answer 25

granulocytopenia (a decrease in | the number of white blood cells)

Question 26

Lithium carbonate is a mood-stabilizing agent which is used to prevent mood swings in patients with

Answer 26

manic-depressive disorder. It is also used to treat mania.

Question 27

The mechanism of action of lithium has not been resolved. Three possibilities are under investigation:

Answer 27

1. Effect on electrolytes and ion transport. 2. Effects on neurotransmitters and the release of neurotransmitters. 3. Effect on second messengers that mediate transmitter action.

Question 28

Lithium is the drug of choice for long-term maintenance to prevent

Answer 28

both manic and depressive | episodes in patients with manic-depressive disorder

Question 29

The safety and efficacy of lithium is enhanced by

Answer 29

monitoring serum lithium concentration

Question 30

Antidepressant Agents-There are several | types of depression and depressions are classified as follows:

Answer 30

Reactive (secondary) depression. This is the most common type and accounts for over 60% of all depressions. ``` Major depression (endogenous). In major depression there are characteristic disturbances of major body rhythms of sleep, hunger and appetite ``` Depression associated with manic-depressive disorder.

Question 31

The major theory which has been proposed to explain major depression is known as the amine hypothesis

Answer 31

Animal studies showed that reserpine inhibited reuptake and storage of serotonin and norepinephrine in the vesicles of presynaptic nerve endings. As a result, there was a depletion of amine stores in these vesicles and amine-dependent neurotransmission would be diminished. Since reserpine induced depression and depleted stores of amine neurotransmitters, it was reasoned that depression might be associated with decreased functional amine dependent neurotransmission.

Question 32

The amine hypothesis does not explain all the effects of antidepressants in depression. The neurotrophic hypothesis suggests that depression is associated with

Answer 32

reduced neurotrophic (growth and inter-connectivity of neurons) support and that antidepressants stimulate neurogenesis and synaptic connectivity in cortical areas.

Question 33

Tricyclic antidepressants: Imipramine is a member of this class of antidepressants which share a

Answer 33

three-ring nucleus

Question 34

Second-generation (atypical) antidepressants: Bupropion and amoxapine, introduced after 1980, are structurally unrelated to the tricyclic antidepressants and were introduced in an attempt to

Answer 34

have available antidepressants with less adverse effects.

Question 35

Selective serotonin reuptake inhibitors (SSRI’s):

Answer 35

The tricyclic antidepressants have anticholinergic (muscarinic), antiadrenergic (alpha), and antihistaminic actions which do not contribute to their efficacy but do contribute to their toxicity. The SSRI’s, in contrast, have much less effect on the autonomic nervous system and therefore have less toxicity.

Question 36

Drugs that block Serotonin and norepinephrine uptake: Drugs such as venlafaxine block transporters for both serotonin and norepinephrine and have an

Answer 36

advantage over the tricyclic | antidepressants due to their better safety profiles. (Less adverse effects).

Question 37

Monoamine oxide (MAO) inhibitors: There are two monoamine oxidase (MAO) enzymes, designated MAO-A and MAO-B. MAO-A is the enzyme primarily responsible for metabolism of

Answer 37

norepinephrine, serotonin and tyramine.

Question 38

MAO-B is more selective for dopamine metabolism. | Selective blockade of MAO-A is therefore

Answer 38

considered more selective for therapy of depression

Question 39

Phenelzine and tranylcypromine are non-selective inhibitors of MAO-A and MAO-B. They combine irreversibly with the enzymes and therefore have a

Answer 39

prolonged duration of action.

Question 40

Moclobemide | is a new

Answer 40

short-acting reversible inhibitor of MAO-A and 90% of the drug appears in urine within 12 hours of administration.

Question 41

In the past, a tricyclic antidepressant such as imipramine has been considered as the drug of first choice for treatment of

Answer 41

depression

Question 42

In recent years, an SSRI such as fluoxetine (Prozac) is often used instead, especially for patients with

Answer 42

major depressive disorder anxiety disorder

Question 43

SSRI’s: The SSRI’s cause nausea, headache, nervousness, and insomnia more commonly than the

Answer 43

tricyclic antidepressants

Question 44

MAO inhibitors: If MAO inhibitors are prescribed, patients must be warned that they interact with dangerous consequences with many other drugs, both prescription and over-the-counter, and with

Answer 44

tyramine-containing food