Psychopharmacy Flashcards
For what conditions are antidepressants suitable?
- unipolar and bipolar depression
- organic mood disorders
- schizoaffective disorder
- anxiety disorders including OCD
- panic
- social phobia
- PTSD
- impulsivity associated with personality disorders
- premenstrual dysphoric disorder
How long does it normally take for antidepressant drugs to become effective?
2-4 weeks
When would you consider switching an antidepressant drug or adding another?
if there is no improvement after a trial of about 2 months and of adequate dose
What advice is there regarding prophylaxis using antidepressants?
- after the first episode continue the drugs for 6months to a year
- second episode continue for 2 years
- third episode discuss life long
What are the 5 main classifications of antidepressant?
- tricyclic antidepressants
- MAOIs
- Selective Serotonin Reuptake Inhibitors (SSRIs)
- Serotonin/Noradrenaline Reuptake Inhibitors (SNRIs)
- Novel antidepressants
What are examples of tertiary tricyclic antidepressants?
- clomipramine
- amitriptyline
Who are tricyclic antidepressants unsuitable for and why?
- have strong anticholinergic properties and are thus unsuitable for the elderly and for patients with benign prostatic hypertrophy, glaucoma, or chronic constipation. All heterocyclics, particularly maprotiline and clomipramine, lower the threshold for seizures.
- lots of side effects!
When would MAOIs be considered for use?
or treating refractory or atypical depression when SSRIs, tricyclic antidepressants, and sometimes even electroconvulsive therapy are ineffective.
What are side effects of MAOIs?
- orthostatic hypotension
- weight gain
- dry mouth
- sedation
- sexual dysfunction
- sleep disturbance
What is meant by the ‘cheese reaction’?
hypertensive crisis can develop when MAOIs are taken with tyramine rich foods or sympathomimetics i.e. must restrict diet by excluding cheese and wine
What is serotonin syndrome?
complication that can occur if MAOIs are taken with other medications that increase serotonin
What are symptoms of serotonin syndrome?
- abdominal pain
- diarrhoea
- sweats
- tachycardia
- hypertension
- myoclonus
- irritability
- delirium
- can lead to hyperpyrexia, cardiovascular shock and death
How can serotonin syndrome be avoided?
- need to wait 2 weeks before switching from an SSRI to an MAOI
- exception is fluoxetine where need to wait 5 weeks because of long half-life
What are SSRIs?
- selective serotonin reuptake inhibitors
- can treat both anxiety and depression
- very safe! Not likely to cause harm if lots taken
What is discontinuation syndrome?
agitation, nausea, disequilibrium and dysphoria arising from coming off SSRIs
What is activation syndrome?
- issue with SSRIs
- increase in serotonin can transiently make the patient more agitated and can last 2-10 days
What can you consider to avoid discontinuation syndrome?
consider switching to fluoxetine as longer half life so may be less profound effect coming off them
What are examples of SSRIs?
- paroxetine
- sertraline
- fluoxetine (prozac)
- citalopram
- escitalopram
- fluvoxamine
What are some side effects of using SSRIs?
- activation syndrome
- discontinuation syndrome
- increased agitation
- sexual dysfunction
- some anticholinergic effects such as dry mouth and some cardiac conduction effects
What do SNRIs do?
inhibit both serotonin and noradrenergic reuptake like the TCAs, but with less side effects
What are SNRIs useful for treating?
- depression
- anxiety
- neuropathic pain
What are examples of SNRIs?
- venlafaxine
- duloxetine
What are common problems associated with SNRI use?
- nausea in first 2 weeks
- may cause increase in blood pressure at high doses (venlafaxine)
What are 2 examples of a novel antidepressant?
- mirtazepine - good augmenting agent
- buproprion-good augmenting agent
What are common problems associated with mirtazepine?
- increase serum cholesterol
- sedating at low doses
- activating at high doses
- associated with weight gain
What are common problems associated with bupropion?
- may increase seizure risk in high doses (avoid in patients with traumatic brain injury, bulimia and anorexia)
- may cause anxiety
- abuse potential
What can be done to combat treatment resistance? (4 options)
- combination of antidepressants e.g. SSRI or SNRI with Mirtazepine
- adjunctive treatment with lithium
- adjunctive treatment with atypical antipsychotic e.g. olanzapine
- ECT!