CNS depression Flashcards
what is depression described as
A reduction of serotonin/dopamine/norephedrine at the synaptic cleft
Risk factors for depression
personal / family hx of depressive illness,
hx of other mental health conditions,
other chronic comorbidities,
female,
recent childbirth,
older age,
psychosocial issues (relationship problems, bereavement, unemployment, poverty, or homelessness)
what does depression severity depend on
intensity, frequency and duration of symptoms, and their impact on daily functioning
tx for mild depression
CBT
tx for mod-severe depression and how long?
antidepressants
note: pt may feel worse in first 1-2 weeks
Take for 4 weeks (6 in elderly) before deemed ineffective
Take for…
6 months after remission
1 year in elderly
2 years in recurrent
what is first line tx for depression
SSRI (fluoxetine, sertraline, citalopram)
fluox if under 17
second line depression tx/ if first line not working
Increase dose
Change SSRI
Mirtazapine
MAO-I (specialist as huge SEs)
TCA/Venlafaxine (severe dep)
Still doesn’t work? Add in lithium OR antipsychotics
what therapy used in severe refractory depression
electroconvulsive therapy
why are SSRIs used as first line despite no clinical evidence? 3 points
Better tolerated
Safer in OD
Safest in patients w/ cardiac events
SERTRALINE= SAFE, CVD
SSRIs- SIDE EFFECTS? GASHBIQ
GI Disturbances
Appetitite/Weight Gain
Sexual Dysfunction
Hyponatraemia
Bleed (avoid NSAIDs, warfarin, PPI key)
Insomnia (take OM)
QT Prolongation (Escitalopram/Citalopram)
SSRIs- INTERACTIONS? (metabolised by CYP enzymes)
C^2QBHS
CYP inhibitors (grapefruit, increases plasma conc.)
CYP inducers (St John’s wort, phenobarbital, phenytoin, less effective)
QT prolongation (amiodarone, sotalol, quinolone- cipro, levo, macrolides)
Bleed risk
Hyponatraemia (carbamazepine, diuretics)
Serotonin Syndrome (Li, mirtazapine)
SEROTONIN SYNDROME? has CAN: cognitive, autonomic effects, neuromuscular excitation.
give symptoms of cognitive
Cognitive: headache, agitation, hypomania, confusion
SEROTONIN SYNDROME? has CAN: cognitive, autonomic effects, neuromuscular excitation.
give symptoms of autonomic
Autonomic: sweating, hyperthermia, nausea, diarrhoea
SEROTONIN SYNDROME? has CAN: cognitive, autonomic effects, neuromuscular excitation.
give symptoms of neuromuscular excitation.
Neuromuscular Excitation: myoclonus, tremor, teeth grinding
WHAT IS SEROTONIN SYNDROME CAUSED BY?
SSRIs, TCAS, MAO-Is
Triptans
Tramadol
Lithium
TRICYCLIC ANTI-DEPRESSANTS
SEDATING? Better for who?
agitated/anxious patients
examples of sedating TCAs
Amitriptyline
Clomipramine
Dosulepin
Trazodone
TRICYCLIC ANTIDEPRESSANTS
LESS SEDATING better for withdrawn/apathetic patients. give 3 examples NIL
Nortriptyline
Imipramine
Lofepramine
TRICYCLIC ANTIDEPRESSANTS
SIDE-EFFECTS? CASHH
Cardiac events
Anti-muscarinic
Seizures
Hypotension
Hallucinations
DANGEROUS IN OVERDOSE
why do tcas have antimuscarinic ses?
tcas block action of ACh at muscarinic receptors
TRICYCLIC ANTIDEPRESSANTS
which are DANGEROUS in OD?
Amitriptyline/Dosulepin- dangerous in overdose, not recommended for depression, specialist-led!
TRICYCLIC ANTIDEPRESSANTS- INTERACTIONS?
CYP inhibitors (grapefruit- increases conc)
CYP inducer (reduces effectiveness)
QT prolongation (amiodarone, sotalol, quinolone)
Anti-muscarinic drugs (oxybutynin, solifenacin, tamsulosin, hyoscine)
Anti-hypertensive drugs
Hyponatraemia
similar to ssris
MAOi initiated by specialist only, what caution to note/ they can cause…
Causes hepatoxicity
(phenelzine+isocarboxazid)
Hypertensive crisis- DO NOT GIVE OTC pseudoephedrine
what otc drug to avoid if pt on maoi
pseudoepehdrine
what food to avoid with pt on maoi
tyramine-rich foods: mature cheese, tofu, salami
MAOi Tranylcypromine + TCA Clomipramine interaction
fatal!!
MAO-I Washout Periods
Other antidepressants should not be started for how long…
Other antidepressants should not be started…
For 2 weeks after last dose of MAOIs (3 weeks if clomipramine/imipramine)
MAO-I Washout Periods
Don’t start MAOI until how long after previous maoi been stopped?
2 weeks after a previous MAOI has been stopped (0 weeks for moclobemide)
MAO-I Washout Periods
Don’t start MAOI until how long after a TCA/ prev antidepressant been stopped?
1-2 weeks after a TCA (3 weeks for clomipramien/imipramine) due to fatal se with trancy
MAO-I Washout Periods
Don’t start MAOI until how long after a SSRI/ prev antidepressant been stopped?
1 week after an SSRI (5 weeks for fluoxetine)
- super long t1/2
how do you switch an SSRI excl fluoxetine to SSRI/SNRI?
direct switch
how do you switch an SNRA i.e. duloxetine/venlafaxine to SSRI/SNRI?
direct switch
how do you switch an SSRI excl fluoxetine to mirtazapine/ TCA?
cross taper
how do you switch an SNRI i.e. duloxetine/venlafaxine to mirtazapine/ TCA?
cross taper
fluoxetine is SSRI with long half life.
how do you switch from it to SSRI/SNRI/ TCA?
stop fluox, start alt 4-7 days later
fluoxetine is SSRI with long half life.
how do you switch from it to mirtazapine
cross taper
how do you switch from mirtazapine to any other antidep?
cross taper
TCA to SSRI (not fluox)/ SNRI/ mirtazapine?
cross taper
TCA to fluox switch?
half dose of TCA
add fluox
slowly stop TCA
