Psych Drugs Flashcards
what can antidepressants be used for?
depression
anxiety disorders
bulimia
neuropathic pain
classifications of antidepressants?
monoamine oxidase inhibitors
monoamine reuptake inhibitors
atypical antidepressants
types of monoamine oxidase inhibitor?
phenelzine (non-selective)
moclobemide (selective)
(not used often)
groups of monoamine reuptake inhibitors?
tricyclics
SSRIs (first line generally)
serotonin + noradrenaline reuptake inhibitors (SNRIs)
types of tricyclics?
amitriptyline notriptyline imipramine lofepramine clomipramine dosulepin
types of SSRI?
fluoxetine escitalopram citalopram sertraline paroxetine
which SSRI is avoided in people with cardio problems and why?
citalopram
risk of prolonged QT (esp when combined with other drugs)
which SSRIs are used first in young people?
fluoxetine = 1st sertraline = 2nd
side effects of SSRIs?
sexual dysfunction vivid dreams increased suicidal ideation in under 25s nausea headache can cause anxiety in first couple weeks sweating hyponatraemia (can be significant in elderly)
types of serotonin + noradrenaline reuptake inhibitor (SNRI)?
venlafaxine
duloxetine
types of atypical antidepressants?
mirtazepine (mixed receptor effect)
bupropion (dopamine uptake inhibitor)
general side effects of monoamine oxidase inhibitors?
can cause hypertensive crisis when combined with tyramine containing foods (eg red wine, cheese etc)
insomnia
postural hypotension
peripheral oedema
general side effects of tricyclics?
anticholinergic effects - dry mouth, urinary retention, dry eyes, blurred vision, constipation sedation weight gain postural hypotension tachycardia cardiotoxic in overdose
how do tricyclics work?
block reuptake of monoamines into pre-synaptic terminals
how do SSRIs work?
block reuptake of serotonin
what are the monoamines?
serotonin
noradrenaline
dopamine?
effects of stopping SSRIs?
flu-like symptoms insomnia nausea imbalance sensory disturbance (hyperarousal)
side effects of SNRIs?
same as SSRIs
how does mirtazepine work and what are its side effects?
blocks alpha 2, 5-HT2 and 5-HT3
causes sedation and weight gain
what is serotonin syndrome?
too much serotonin in the synapses, usually due to drug effects
what drugs can cause serotonin syndrome?
antidepressants
analgesics (tramadol etc)
antiemetics
recreational drugs
symptoms of serotonin syndrome?
autonomic instability (fluctuating BP, HR and temp, sweating etc) neuromuscular abnormality (tremor, clonus, hypertonic, hyperreflexia) mental state changes (delirium, agitation, pressured speech, confusion, coma etc)
what can serotonin syndrome be confused with?
catatonia
neuroleptic malignant syndrome
organic causes
how is serotonin syndrome managed?
stop causative drug
overall summary of depression management?
1st line = SSRI
2nd line = switch to another SSRI or SNRI
3rd line = switch to mirtazepine or augment SSRI/SNRI with another drug
4th line = try a different augmentation drug
what drugs can SSRIs/SNRIs be augmented with?
mirtazepine antipsychotics (atypicals) lithium T3 bupropion
risks when using 2 antidepressants?
serotonin syndrome
how do you start treatment with antidepressants?
start drug an titrate to effective dose (often around 20mg)
reassess after 2 weeks of effective dose
if dose is effective then continue for 6-9 months
what do you do if no effect after 2 weeks of antidepressants?
reassess after another 1-2 weeks then consider increasing dose if still no improvement
if still no effect after dose increase then change drug
how is panic disorder managed?
1st line = SSRI
2nd line = tricyclics
also do CBT
(dont use benzodiazepines?)
how is GAD managed?
1st line = SSRI
2nd line = SNRI or pregabalin benzodiazepines for acute episodes
also do CBT
how is OCD managed?
1st line = intensive CBT + exposure response therapy (+/- SSRI)
2nd line = clomipramine
3rd line = clomipramine + citalopram, may add atypical antipsychotic
how do benzodiazepines work?
block GABA receptors
effects of benzodiazepines?
hypnosis/sedation
muscle relaxant
anticonvulsant
anterograde amnesia
symptoms of benzodiazepines withdrawal?
abdo cramps anxiety/panic attacks physical symptoms (muscle tension, pain, palpitations, sweating, shaking) blurred vision depression insomnia dizziness headache difficulty concentrating nausea and vomiting tingling in hands and feet restlessness sensory sensitivity
main risk of lithium?
narrow therapeutic window so can cause toxicity
therefore need to monitor bloods
side effects of lithium?
dry mouth metallic taste polyuria and polydipsia fine tremor hypothyroid long term renal dysfunction weight gain nephrogenic diabetes insipidus
effects of lithium toxicity?
vomiting diarrhoea ataxia course tremor drowsiness convulsions
what are the 3 main anticonvulsants?
sodium valproate
lamotrigine
carbamazepine
side effects of sodium valproate?
drowsiness ataxia cardio effects hepatic enzyme inducer teratogenic (neural tube defects)
side effects of carbamazepine?
drowsiness
ataxia
cardio effects
hepatic enzyme inducer
side effects of lamotrigine?
small risk of stevens johnson syndrome
how do antipsychotics work in general?
dopamine antagonists + 5-HT antagonists
general side effects of antipsychotics?
sedation
weight gain
metabolic syndrome
extra-pyramidal effects
extra-pyramidal effects?
dystonia (sustained contraction)
akathisia (restlessness)
parkinsonism
tardive dyskinesia
how do atypical antipsychotics work?
block dopamine and 5-HT
why are atypical antipsychotics generally better than typical ones?
less likely to cause extra-pyramidal side effects
better efficacy against negative symptoms
types of atypical antipsychotics?
olanzapine quetiapine risperidone clozapine aripiprazole amisulpride
which atypical antipsychotic should generally be avoided in people with cardio risk factors (overweight, diabetic, high cholesterol, high BP etc)
olanzapine
causes weight gain and increased triglycerides and cholesterol
increased blood glucose
general rule for antipsychotic prescribing in schizophrenia?
try 2 atypicals first then clozapine if not working
when is clozapine used?
treatment resistant schizophrenia
risks of clozapine?
agranulocytosis (immediate FBC if they get a sore throat)
myocarditis and cardiomyopathy
long QT
side effects of clozapine?
dizziness/drowsiness hypersalivation erectile dysfunction hyperprolactinaemia hypotension
management of acute bipolar presentation?
- stop antidepressant
- consider antipsychotic (if not already taking anti-manic drug)
- check anti-manic drug dose and compliance, increase dose, add lithium/valproate, and can add antipsychotic and short acting benzo if needed (if already taking anti-manic drug)
steps in long term management of bipolar?
- lithium
- valproate (not in young women) or olanzapine/quetiapine
- alternative antipsychotic, carbamazepine, lamotrigine
try to avoid long term antidepressant if possible
how is schizophrenia management initiated?
- atypical antipsychotic and reassess after 2-3 weeks, if effective then continue for 18 months - 2 years
- try another antipsychotic (typical or atypical) and reassess after 2-3 weeks, if effective then continue for 18 months - 2 years
- clozapine
what defines treatment resistant schizophrenia?
no response to 2 antipsychotics including an atypical one
how is dopamine related to schizophrenia?
drug which release dopamine produce psychotic like state
therefore amphetamines and levodopa etc can make schizophrenia worse
what is neuroleptic malignant syndrome?
rare but serious side effect of dopamine blockade which can occur in use of antipsychotics
how is neuroleptic malignant syndrome managed?
stop drug therapy
dopamine agonist used to reverse blockade
symptoms of neuroleptic malignant syndrome?
fever tachycardia irregular pulse tachypnoea altered mental state muscle rigidity autonomic dysfunction (can have high or low BP)
