Pharmacology: Antidepressants and Mood Stabilisers Flashcards
What prescribed drugs can exacerbate/worsen depression
steroids
How do more anti depressents likely work
- blocking re uptake of monoamine neurotransmitter
- preventing breakdown of monoamine neurotranmitters
- as a result the is and increase neurotransmitter availability (in the short term)
Name examples of SSRIs
Fluoxetine, paroxetine, citalopram, escitalopram, sertraline, fluvoxamine
When are SSRIs used
depression panic disorders PTSD OCD chronic pain eating disorders stroke premature ejactuation
How do SSRIs work
Inhibit the reuptake of the monoamine serotonin (5HT) within the synapse
How long do SSRIs take to work
2-3 weeks
What are the clinical aspects to remember when prescribing SSREs
Can usually be started at therapeutic dose from day one
relatively safe in overdose
Fluoxetine etc inhibit CYP450 which causes interactions with other drugs which work via the same pathway
What are the most common side effects realting to SSRIs
Sexual dysfunction
GI side effects
short term anxiety
in young people there is increased risk of self harm in first few weeks
How can sexual dysfunction due to SSRI’s be reversed
by 5ht antagonists
eg Trazodone
What are the adverse effects of tricyclics
Constipation dry mouth cardiac function postural hypotension (all due to unwanted receptor activity, typically anticholinergic)
name some monoamine oxidase inhibitors
Phenelzine, isocarboxazid, tranylcyprromide
What does MAO A metabolise
NA, 5 HT and tyramine
what does MAO B metabolise
DA, tyramine, phenylethylamine
When are MAOIs used
Atypical depression
Third/fourth line treatment
What is the main adverse affect of MAOI
cancause hypertensive crises due to now increased levels of tyramine (which releases NA)
What are the symptoms of a hypertensive crisis
flushing
headache
increased BP
rarely CVA
how is a hypertensive crisis treated
alpha blockade
eg phentolamine
chlorpomazine
What antidepressant can result in extra pyramidal side effects
Paroxetine - due to affect on DA
What anti psychotic can be antidepressant at low doses
flupentixol
Why should antidepressants be stopped slowly
there is a potential to develop a discontinuity syndrome (SSRI’s particularly) if stopped suddenly
shivering, anxiety, headache, dizziness
Name examples of SNRIs
venlafaxine
duloxetine
Name an NSSA
mirtazapine
What drugs all work on GABA receptors
Ethanol Benzodiazepines Baclofen Valproate Pregabalin Gabapentin
What are mood stabilisers
‘anti convulsant drugs- are more effective at treating mania than depression
Name mood stabilisers
Carbamazepine
Valproate
Lamotrigine
Lithium
name atypical antipsychotics
Olanzapine
risperidone
How does lamotrigine work
blocking sodium channels
reduces excitability and cell firing
Why is lithium not as commonly used now?
high incidence of adverse effects and toxic in overdose
poor adherence
requires blood monitoryin
How do first generation anti psychotics work
on D2 receptors- DA blockade
What is the main side effect in typical antipsychotics
movement disorders
hyperprolactinaemia
name a typical antipsychotic
haloperadol
