Psychiatry Drugs Flashcards
How long do anti-depressants typically take to work
4-6 weeks
How is non-response to an anti-depressant defined
No response or inadequate response after six weeks at the maximum BNF dose or highest tolerated dose
How long should you continue treatment after full resolution of symptoms after a first episode
6-12 months
How long should you continue treatment after full resolution of symptoms after a second episode
12-24 months
How long should you continue treatment after full resolution of symptoms after a third recurrence
Continue indefinitely if willing
What is the mainstay of treatment for Bipolar Disorder
Mood stabiliser (lithium) + anti-convulsant + anti-psychotic
What should you never give on its own for someone with Bipolar disorder and why not
Anti-depressant should not be given without a mood stabiliser
Can set patient to rapid cycling bipolar
What does SSRI stand for
Selective Serotonin Reuptake Inhibitor
Give 3 examples of SSRI’s
Citalopram, Fluoxetine, Sertraline
What is the first line drug treatment for major depressive disorder
SSRI’s
What side effect can SSRIs cause in elderly patients
Hyponatraemia
What side effect can SSRIs cause in under 25’s
Transient increase in self-harm / suicidal ideation
What time of day should SSRIs be taken
In the morning
to avoid insomnia
Name some general SSRI side effects
GI upset, anxiety, agitation, insomnia, sexual dysfunction
What is there an increased risk of, if SSRIs are taken with NSAIDS
GI bleeding
Which SSRI is safest in a patient with cardiac problems
Sertraline
Which SSRI is safest in a patient with epilepsy
Citalopram
What is the mechanism of action of SSRIs
Selectively inhibit reuptake of serotonin (5-HT) from the synaptic cleft
What class of drug is Amitriptyline
Tricyclic Antidepressant
Name 3 tricyclic antidepressants (not amitriptyline)
Imipramine
Clomipramine
Dosulepin
Why are tricyclic antidepressants not the first line for depression despite being as effective as SSRIs
Cardiac side effects
Dangerous in overdose
What effect do tricyclics have on weight
Weight gain
What time of day should tricyclics be taken
At night due to sedation side effect
Name some anticholinergic effects and which anti-depressant drug class can cause these
Tricyclic antidepressants can cause: Blurred vision Dry mouth Constipation Urinary retention
What kind of drug is Mirtazapine
Noradrenergic and Specific Serotonergic Antidepressant (NaSSA)
When could Mirtazapine be used 1st line in depression
May be used first line if the patient has insomnia and/or poor appetite
What is a characteristic side effect of Mirtazapine
Increase in appetite
When should Mirtazapine be taken
Night time due to sedation effect
Which anti-depressant can cause GI upset when taken with alcohol
Mirtazapine
What does SNRI stand for
Serotonin Noradrenaline Reuptake Inhibitor
How do SNRIs work
Block the reuptake of monoamines (noradrenaline and 5-HT) into presynaptic terminals
Name 2 SNRIs
Duloxetine
Venlafaxine
Which drug combination can be very very effective in treating depression which hasn’t responded to SSRI’s
Mirtazapine + Venlafaxine
“california rocket fuel”
Which SNRI can also be used to treat neuropathic pain and bladder instability
Duloxetine
What time of day should SNRIs be taken
Morning to avoid insomnia side effect
What are the side effects of SNRIs
Similar to SSRIs:
GI upset, anxiety, agitation, insomnia, sexual dysfunction
What does MAOI stand for
Monoamine oxidase inhibitor
How do MAOIs work
Inhibitors of MAO-A and B
-> decreased breakdown of the monoamine neurotransmitters (norepinephrine, serotonin, dopamine) leading to increased levels in the synapse
What are the differences between reversible and irreversible MAOIs
Reversible MAOIs are typically less effective but also have fewer side effects
Name a reversible MAOI
Moclobemide
Name an irreversible MAOI
Phenelzine
What are some minor side effects of MAOIs
Postural Hypotension
Insomnia
Peripheral oedema
What is the major side effect of MAOIs (concerning diet)
Hypertensive crisis
Which amine can cause a hypertensive crisis as a side effect of MAOIs
Tyramine
How does a hypertensive crisis occur when a patient is on an MAOI
Tyramine is a potent releaser of norepinephrine -> elevated BP. Normally MAO-A breaks down norepinephrine. If MAO-A is inhibited and a high-tyramine meal is taken, norepinephrine can accumulate and cause a hypertensive crisis
What are some symptoms of a hypertensive crisis
Headache, shortness of breath, nosebleed, anxiety. Can lead to arrhythmias, stroke, seizures, death
What sort of foods have a high tyramine content
Red meats, cheese, wine
How is hypertensive crisis treated
Phentolamine infusion (alpha-adrenergic antagonist)
What is Trazodone
Serotonin 2 antagonist/reuptake inhibitors (SARI)
When would Trazodone be used
Often used when sedation is needed and/or to augment other antidepressants
When should Trazodone be taken
Should be taken at night due to sedation
What are some side effects of Trazodone
GI upset, dizziness, sedation, tiredness, headache
What is the most effective treatment for Bipolar disorder
Lithium carbonate
What is the mode of action of Lithium (don’t bother about this too much)
May block phosphatidylinositol pathway (second messenger system) or inhibit Glycogen Synthase Kinase 3β
Why must 12-hour post-dose blood levels be measured when a patient is on lithium
Because of lithium’s narrow therapeutic index
What are some side effects of Lithium
Dry mouth / strange taste Polydipsia & polyuria Tremor Hypothyroidism Weight gain
Which endocrine condition can lithium cause as a side effect
Nephrogenic diabetes insipidus
When should lithium be taken
At night due to sedation
What are some toxic effects of lithium
Vomiting Diarrhoea Ataxia / coarse tremor Drowsiness Convulsions Coma
What is the treatment of lithium toxicity
Stop lithium
IV fluids
Monitor renal function
What kind of drug is Sodium Valproate
Anti-convulsant
How does sodium valproate work
Blocks voltage sensitive sodium channels, increases levels of GABA
What are some side effects of sodium valproate
sedation, tremor, dizziness, GI upset, tiredness, weight gain. Rarely hepatotoxicity, pancreatitis, increase in suicidal behaviour
Why should sodium valproate not be given to women of childbearing age
Teratogenic
Name an anticonvulsant apart from sodium valproate
Lamotrigine
How does Lamotrigine work
Blocks voltage sensitive sodium channels
What are some common side effects of Lamotrigine
GI upset, insomnia, sedation (not common), dizziness, ataxia, tiredness
What is a potentially fatal side effect of Lamotrigine
Stevens-Johnson syndrome
Name 2 typical antipsychotics
Haloperidol
Chlorpromazine
Name 2 atypical antipsychotics
Quetiapine
Olanzapine
How do antipsychotics work
Block D2 receptors
What are the possible drug treatments for Generalised Anxiety Disorder (GAD)
SSRI/SNRI
Pregabalin
Benzodiazepines (short term only)
What are the possible drug treatments for Panic Disorder
SSRI/SNRI
Tricyclic
Benzodiazepines (short term only)
Which tricyclic antidepressant can be used to treat Obsessive Compulsive Disorder
Clomipramine
Which receptor do benzodiazepines act on
GABA-A
Which substances also act on the GABA-A receptor
Alcohol
Barbituates
Which ion channel is the GABA-A receptor linked to
Chloride ion (allows influx when stimulated)
