Pharmacology Flashcards
Clinical uses for Antidepressants?
- Moderate to severe depression
- Dysthmia (persistent mild depression)
- Generalised anxiety disorder
- Panic disorder, OCD, PTSD
- Neuropathic pain
- Bulimia nervosa
Examples of antidepressant drugs?
- 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
What is the role of serotonin and it’s receptors (5HT1-5HT7)?
Involved in regulation of sleep, appetite, mood and pleasure.
Where is serotonin produced in the CNS?
Raphe nuclei in the brainstem.
Monoamine oxidase inhibitors examples?
Phenelzine and moclobemide
Monoamine oxidase inhibitor mode of action?
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.
Common side effects of MOA inhibitors?
- Insomnia
- Postural hypotension
- Peripheral oedema
- Potentiates effects of other drugs (e.g. barbiturates) by decreasing metabolism.
Tricyclic antidepressant examples?
Dosulepin, amytriptyline.
Tricyclic antidepressant mode of action?
Block the re-uptake of monoamines (mainly noradrenaline and 5-HT) into presynaptic terminals.
Tricyclic antidepressant side-effects?
- Sedation
- Weight gain
- Cardiotoxic if in overdose
- Cardiovascular - postural hypotension, tachycardia and arrhythmias.
- Anticholinergic - blurred vision, dry mouth, constipation and urinary retention.
Selective serotonin re-uptake inhibitor (SSRI) examples?
Fluoxetine, citalopram/escitalopram
SSRI common side-effects?
- Nausea
- Headache
- Worsening anxiety
- Sweating/vivid dreams
- Sexual dysfunction
- Hyponatraemia (in elderly)
SSRI mode of action?
Selectively inhibit re-uptake of serotonin (5-HT) from synaptic cleft.
Acute aim of bipolar affective disorder treatment?
Reduce mood in episodes of mania
Raise mood in episodes of depression
Long term aim of bipolar affective disorder treatment?
To stabilise mood and prevent recurrence of mania and depression (prophylaxis)
Lithium is normally given as lithium carbonate. True/false?
True
Lithium mode of action?
May block phosphatidylinositol pathway (second messenger system) or inhibit Glycogen Synthase Kinase 3β or modulate NO signalling
Side-effects of lithium?
Dry mouth / strange taste
Polydipsia & polyuria
Tremor
Hypothyroidism
Long term reduced renal function
Nephrogenic diabetes insipidus
Weight gain
Toxic effects of lithium?
Vomiting
Diarrhoea
Ataxia / coarse tremor
Drowsiness / altered conscious level
Convulsions
Coma
Examples of anticonvulsants that can be used as mood stabilisers?
Valproic acid, lamotrigine and carbamazepine which can be used in long term treatment.
Anticonvulsant mode of action in mood stabilising?
Very unclear, perhaps potentiate GABA transmission and therefore block overactive pathways (kindling model of bipolar disorder)
Side effects of anticonvulsant medication?
Valproate & carbamazepine: drowsiness, ataxia, cardiovascular effects, induces liver enzymes
Valproate: teratogenicity (neural tube defects)
Lamotrigine: very small risk of Stevens-Johnson syndrome
Examples of antipsychotics as mood stabilisers?
Quetiapine, Aripiprazole, Olanzapine, Lurasidone
Mode of action of antipsychotics as mood stabilisers?
Dopamine antagonism + 5-HT antagonism
Side-effects of antipsychotics as mood stabilisers?
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).
