Drugs of Dependence and Antidepressants 2 Flashcards Preview

MD1 Neuroscience > Drugs of Dependence and Antidepressants 2 > Flashcards

Flashcards in Drugs of Dependence and Antidepressants 2 Deck (51):
1

What receptor does LSD act on?

Various 5-HT receptors

2

What mediates LSD's psychotomimetic effects?

5-HT2A receptor agonist actions

3

What does LSD's agonist activity at the 5-HT2A receptor cause?

Release of glutamate in cortex

4

What is the effect of LSD in the raphe nuclei?

Inhibits firing of 5-HT containing neurons

5

How does LSD inhibit the firing of 5-HT containing neurons in the raphe nuclei?

Acts as agonist on inhibitory autoreceptors of these cells

6

What are affective disorders?

Those that influence mood

7

What is unipolar/major depression?

Extreme melancholia and withdrawal

8

What is reactive depression?

Due to known cause

9

What is endogenous depression?

No known/apparent cause

10

What is bipolar depression?

Mood swings from extreme elation and hyperexcitability to extreme melancholia and withdrawal

11

What does the monoamine theory of depression state?

Drugs that interfere with monaminergic transmission influence mood

12

What are the monoamine transmitters?

Noradrenaline
Serotonin
Dopamine

13

What does a depletion in monoamine transmitters cause?

Depression

14

What does an acute elevation of monoamine transmitters in the synapse do?

Can enhance mood

15

Why do drugs that elevate mood not necessarily make good antidepressants?

Dependence - dopamine related
Toxicity
- Cardiovascular because given systemically
- Psychoses with overuse

16

How long can antidepressants take to take effect?

2-6 wks

17

What are the first generation drugs used to treat unipolar depression?

Tricyclic antidepressants = "ipramines"
Monoamine oxidase (MAO) inhibitors

18

What are the second generation drugs used to treat unipolar depression?

Selective serotonin uptake inhibitors (SSRIs)
Selective serotonin/noradrenaline uptake inhibitors (SSNRIs)

19

What are the third generation drugs used to treat unipolar depression?

Atypical antidepressants
- Novel monoaminergic drugs
- Non-monoaminergic drugs

20

What drugs are used to treat bipolar depression?

Lithium
Some antiepileptics; eg: carbamazepine

21

What are the pharmacological actions of tricyclic antidepressants?

Inhibit neuronal uptake of noradrenaline and serotonin
Antagonise
- Alpha adrenoceptors
- Muscarinic receptors
- Histamine receptors
- Serotonin receptors
Quinidine-like membran stabilising action at very high concentrations > acts as local anaesthetic

22

How long do the clinical effects of tricyclic antidepressants take to develop?

Wks despite pharmacological effects taking hrs

23

What is likely to underly the antidepressant activity of tricyclic antidepressants?

Adaptive changes in neuronal function
- Change in receptor sensitivity/density
- Change in 2nd messenger activity

24

What is the therapeutic window of tricyclic antidepressants?

Narrow > limited efficacy

25

What is the consequence of the longish half-life of tricyclic antidepressants?

Gradual accumulation possible
Slowly developing side effects

26

What are the side effects of tricyclic antidepressants?

Sedation
Anti-cholinergic = SLUD
Postural hypotension
Weight gain

27

What happens in overdose of tricyclic antidepressants?

Confusion
Mania
Cardiac dysrhythmias
Seizures
Impotence

28

What is the pharmacological effect of MAO inhibitors?

Increase levels of
- Noradrenaline
- Serotonin
- Dopamine

29

Are MAO inhibitors slow or fast acting?

Delayed antidepressant effect

30

Do MAO inhibitors reversible or irreversible?

Irreversible

31

What is the cheese reaction?

Monoamine oxidase present in gut wall to break down dietary amines (mainly tyramine)
Tyramine can release noradrenaline from storage vesicles in peripheral nerve terminals > indirectly sympathomimetic
MAO inhibitors stop breakdown of tyramine > absorbed > enhanced sympathomimetic effect

32

Where is tyramine commonly found?

Cheese
Wines
Chocolate
Bananas

33

What are the sympathomimetic effects of the cheese reaction?

Acute hypertension
Throbbing headache
Intracranial haemorrhage

34

What is moclobemide?

MAO inhibitor - most commonly used
Monoamine oxidase A selective > prefers noradrenaline and serotonin
Reversible
Less likely to cause cheese reaction
Interaction with other drugs

35

What are the side effects of moclobemide?

Dizziness
Nausea
Insomnia

36

What are some examples of SSRIs?

Fluoxtine = prozac
Paroxetine
Sertraline

37

What is the selectivity for SSRIs?

Selective for 5-HT uptake
Few adrenergic, histaminergic, and cholinergic actions

38

What is the therapeutic index of SSRIs?

High

39

What is the toxicity of SSRIs?

Minimal unless combined with other drugs

40

What is the serotonin syndrome?

SSRI + MAO inhibitor + tricyclic antidepressant
Highly anxious
Hyperthermia
Muscle rigidity
Cardiovascular collapse

41

What effect do SSRIs have in adolescents?

Anxiety and suicidal tendencies on commencement

42

What are the side effects of SSRIs?

Nausea
Insomnia
Agitation
Weight change
Loss of libido

43

What is venlaflaxine?

SSNRI

44

What is reboxetine?

Atypical antidepressant
Monoaminergic mechanism: re-uptake inhibitor

45

What is mianserin?

Atypical antidepressant
Monaminergic mechanism: blocks alpha2 adrenoceptors, histamine, and serotonin receptors

46

What is mirtazepine?

Atypical antidepressant
Monoaminergic mechanism: blocks alpha2 adrenoceptors and serotonin receptors
Good for people with low mood with basis in anxiety

47

What are some pro-cognitive therapies used in the treatment of depression?

Breathing exercise
Physical exercise
Deep brain stimulation

48

What could be the long term changes of depression be caused by, and what should new drug targets focus on?

Long term changes because of neuronal death
Targets should include focus on cell survival

49

What is the pharmacological effect of lithium carbonate?

Interaction with inositol phosphate 2nd messengers
Tends to reduce Ca in nerves

50

What is the therapeutic index of lithium carbonate?

Very low
Plasma levels must be monitored

51

What are the side effects of lithium carbonate?

Nausea
Tremor
Impaired renal, thyroid, and neurological function

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