Antidepressants Flashcards
what are the causes of depression in regards to neurotransmitters
likely reduction in SEROTONIN RECEPTORS in hippocampus
what do mono amine oxadase inhibitors do
inhibit MAO enzyme activity
MAO breaks down norepinephrine/ serotonin/ dopamine
therefore inhibiting MAO increases transmitter levels
what are some MAOI
Phenelzine
selegiline
tranylcypromine
what can selegiline be used for as well as depression
parkinsons
what are some side effects of MAOI
weakness
dizziness
headache
fatigue
weight gain
impotence
what are some interactions of MAOI
DRUGS
do not use with SSRI/ tricyclic/ analgesics - morphine/tramadol
this will increase serotonin to dangerous levels (confusion, tremor, coma, death)
14 day washout period
FOOD- if high in tyramine can cause high blood pressure crisis
cheese
venison
alcohol
green veg (broad beans)
what is the washout period for MAOI
14 days
what is moclobemide
it is a reversible MAOI
acts by reversible inhibition of MAO type A
not prescribed in primary care
has less effect from tyramine
what is the washout period of moclobeminde
7 days
it is a short acting med
how do tricyclic antidepressants work
they inhibit the re-uptake of norepinephrine and serotonin by blocking the transporters that are responsible for re-uptake of these neurotransmitters
therefore this increases the concentration on NT in synapses–> further neurotransmission
what are tricyclics used for
depression
anxiety
chronic pain (fibromyalgia, reflex sympathetic dystrophy syndrome)
IBS
Neuralgia
OCD
Nocturnal enuresis
PTSD
what side effects can tricyclic antidepressants cause
risk of arrythmias (if CV disease)
reduce intestinal mobility (have antimuscarinic activity- blocks muscarinic acetylcholine receptor activity)
induce brady, then tachycardia
reduce bronchial secretions
urinary retention
dry mouth
confusion
name some tricyclic antidepressants
amitriptyline
clomipramine
imipramine
lofepramine
nortriptyline
what are tricyclic antidepressants mainly used for now
chronic pain
name a drug related to tricyclics
trazodone
it is more sedating
why should you be concerned when prescribing trazadone
very dangerous in overdose and so be careful how much you prescribe
use with caution in patients at high risk of suicide in case overdose
how do SSRI work
limit re-absorption of serotonin
only have a weak affinity for norepinephrine and dopamine transmitters
what are the serotonin receptors known as
5-hydroxytryptamine
5-HT
what are SSRIs prescribed for
depression
anxiety
OCD
panic disorder
PTSD
eating disorders
menopausal symptoms
what do the SSRI receptors do and where are they found
found in the pns and cns (excitatory and inhibitory neurotransmission)
they modulate the release of many neurotransmitters
GABA, dopamine, epinephrine, norepinephrine, ach
they influence aggression, anxiety, cognition, learning memory, mood and sleep
what are the side effects of SSRIs
reduced libido, dysfunction
bleeding- affects anticoagulants, increase GI bleeds
cardiac issues (eg. citalopram and QT interval prolongation)
suicide (particularly under 18, therefore only prescribed my a psychiatrist)
overdose (but safer than most)
epilepsy- reduced fit threshold
nausea
rash
muscle aches
insomnia
sweating
name SSRIs from most toxic to least
citalopram
escitalopram
paroxetine
sertraline
fluoxetine
Name a serotonin norepinephrine up-take inhibitor and its uses
Duloxetine
depression
neuropathic pain
stress urinary incontinence
what are some side effects of duloxetine
nausea
insomnia
dizziness
what is mirtazapine, its uses and side effects
presynaptic alpha2-adrenoreceptor antagonist
and a noradrenergic and specific serotonergic antidepressant
depression, anxiety, PTSD
low- drowsiness
high- more stimulant effect
what is venlafaxine and its uses
serotonin-norepinephrine re-uptake inhibitor
major depressive disorder
anxiety
panic
social phobia
resistant depression
it is metabolised in the body by desvenlafaxine (by cytoP206 isoenzyme in the liver)
what is lithium used for and its side effects
bipolar/ mania mood stabalisation
adverse kidney and thyroid affects
what antidepressants are commonly used for pain
amitriptyline
nortriptyline
duloxetine- also for diabetic neuropathy
how to antidepressants work with pain
they have a direct effect on the mechanisms of pain
tricyclics block the re-uptake of noradrenaline and serotonin (5-HT) into the nerve endings and increase their levels in the pain control pathways
useful for nerve damage/ abnormal nerve function/ muscle pain
good effect on pain sleep effects
when is there a risk of torsades de pointes with antidpressants
citalopram (prolong QT)
use of nore than one drug that prolongs QT increases this and ventricular arrhythmias
who have more risk factors for qtc prolongation and therefore vulnerable to drug-induced LQTS
major psychiatric disorders
CV disease
women
elderly
what are some drugs that prolong qt
erythromycin
clarithromycin
fluconazole
sotalol
amiodarone
methadone
risperidone
doxepin
domperidone
