Pharmacology

Question 1

Clinical uses for Antidepressants?

Answer 1

• Moderate to severe depression
• Dysthmia (persistent mild depression)
• Generalised anxiety disorder
• Panic disorder, OCD, PTSD
• Neuropathic pain
• Bulimia nervosa

Question 2

Examples of antidepressant drugs?

Answer 2

• Monoamine oxidase inhibitors
• Monoamine re-uptake inhibitors
  
  • Tricyclics
  • Other non-selective re-uptake inhibitors.
  • Selective serotonin re-uptake inhibitors.
  • Noradrenaline re-uptake inhibitors
• Atypical drugs

Question 3

What is the role of serotonin and it’s receptors (5HT1-5HT7)?

Answer 3

Involved in regulation of sleep, appetite, mood and pleasure.

Question 4

Where is serotonin produced in the CNS?

Answer 4

Raphe nuclei in the brainstem.

Question 5

Monoamine oxidase inhibitors examples?

Answer 5

Phenelzine and moclobemide

Question 6

Monoamine oxidase inhibitor mode of action?

Answer 6

Irreversible (phenelzine) or reversible (moclobemide) inhibitors of MAO - A and B.

MAO - A and B are enzymes that remove and inhibit brain neurotransmitters such as dopamine, serotonin and noradrenaline.

Question 7

Common side effects of MOA inhibitors?

Answer 7

• Insomnia
• Postural hypotension
• Peripheral oedema
• Potentiates effects of other drugs (e.g. barbiturates) by decreasing metabolism.

Question 8

Tricyclic antidepressant examples?

Answer 8

Dosulepin, amytriptyline.

Question 9

Tricyclic antidepressant mode of action?

Answer 9

Block the re-uptake of monoamines (mainly noradrenaline and 5-HT) into presynaptic terminals.

Question 10

Tricyclic antidepressant side-effects?

Answer 10

• Sedation
• Weight gain
• Cardiotoxic if in overdose
• Cardiovascular - postural hypotension, tachycardia and arrhythmias.
• Anticholinergic - blurred vision, dry mouth, constipation and urinary retention.

Question 11

Selective serotonin re-uptake inhibitor (SSRI) examples?

Answer 11

Fluoxetine, citalopram/escitalopram

Question 12

SSRI common side-effects?

Answer 12

• Nausea
• Headache
• Worsening anxiety
• Sweating/vivid dreams
• Sexual dysfunction
• Hyponatraemia (in elderly)

Question 13

SSRI mode of action?

Answer 13

Selectively inhibit re-uptake of serotonin (5-HT) from synaptic cleft.

Question 14

Acute aim of bipolar affective disorder treatment?

Answer 14

Reduce mood in episodes of mania

Raise mood in episodes of depression

Question 15

Long term aim of bipolar affective disorder treatment?

Answer 15

To stabilise mood and prevent recurrence of mania and depression (prophylaxis)

Question 16

Lithium is normally given as lithium carbonate. True/false?

Answer 16

True

Question 17

Lithium mode of action?

Answer 17

May block phosphatidylinositol pathway (second messenger system) or inhibit Glycogen Synthase Kinase 3β or modulate NO signalling

Question 18

Side-effects of lithium?

Answer 18

Dry mouth / strange taste
Polydipsia & polyuria
Tremor
Hypothyroidism
Long term reduced renal function
Nephrogenic diabetes insipidus
Weight gain

Question 19

Toxic effects of lithium?

Answer 19

Vomiting
Diarrhoea
Ataxia / coarse tremor
Drowsiness / altered conscious level
Convulsions
Coma

Question 20

Examples of anticonvulsants that can be used as mood stabilisers?

Answer 20

Valproic acid, lamotrigine and carbamazepine which can be used in long term treatment.

Question 21

Anticonvulsant mode of action in mood stabilising?

Answer 21

Very unclear, perhaps potentiate GABA transmission and therefore block overactive pathways (kindling model of bipolar disorder)

Question 22

Side effects of anticonvulsant medication?

Answer 22

Valproate & carbamazepine: drowsiness, ataxia, cardiovascular effects, induces liver enzymes

Valproate: teratogenicity (neural tube defects)

Lamotrigine: very small risk of Stevens-Johnson syndrome

Question 23

Examples of antipsychotics as mood stabilisers?

Answer 23

Quetiapine, Aripiprazole, Olanzapine, Lurasidone

Question 24

Mode of action of antipsychotics as mood stabilisers?

Answer 24

Dopamine antagonism + 5-HT antagonism

Question 25

Side-effects of antipsychotics as mood stabilisers?

Answer 25

Sedation, weight gain, metabolic syndrome

Extra-pyramidal side-effects (Aripiprazole) i.e. dystonia (continuous spasms and muscle contractions), akathisia (may manifest as motor restlessness), parkinsonism characteristic symptoms such as rigidity, bradykinesia (slowness of movement), tremor, and tardive dyskinesia (irregular, jerky movements).