Pharm Flashcards
Pharm antidep SSRI
MoA: presynaptic blockade of serotonin reuptake pumps
SE: GI disturbance, anxiety +agitation, insomnia, wt loss, sexual dysfunction, inc. risk of bleeding
Pharm antidep NaSSA
moa: noradrenergic specific serontinergic antidepressant (presynaptic a2 blockade results in increased NA and 5-HT)
SE: sedation, wt gain, inc. appetite
Pharm antidep TCA
High sedation: amitriptyline, clomipramine, dosulepin, tradazone
Low sedation: imipramine, lofepramine, nortriptyline
MoA: Presynaptic NA + 5-HT reuptake pump blockage, block of muscarinic, histaminergic and a-adrenergic Rs
SE: dry mouth, constip., postural hypotension, wt gain, QT pronlongation, arrhythmia, destabilising BPAD
Pharm antidep MAO-A
Eg. selegiline, phenelzine, moclobemide (reversible)
MoA: inhibits MOA-A -> inc. synaptic NA, 5-HT, DA
Risk: cheese reaction, cant break down tyramine causes hypertensive crisis
Pharm antidep Lithium
Renal excretion
drugs that affect level: diuretic, NSAID, ACEi
Pharm antipsych typical (1st gen)
e.g. Haloperidol, chlorpromazine, flupentixol, zuclopethixol
MoA: block D2R in mesolimbic
SE: EPSE (acute dystonia, tardive dyskinesia, akathisia, Parkinsonism, hyperprolactin aemia)
Pharm antipsych atypical (2nd Gen)
Eg Clozapine, olanzapine, risperidone, quetiapine, apiprazole. amisulpride
Pharm antipsych Clozapine
Used in Treatment resistant schizophrenia
MoA: blocks D1+4R
CI: prev./current neutropenia, hx myocarditis, active/progressive liver Dx
SE: sedation, wt gain, reduced seizure thresh, myocarditis, metabolic synd.
NB. smoking cessation decreases CYP450 levels and raises clozapine level
Register pt w/clozaril pt monitoring service
Ensure normal leucocyte count and ECG before Rx
FBC: wkly for 18wk, 2wkly for 1yr, monthly after
EPSE Rx
Acute dystonia: procyclidine (anitchol.)
Pseudoparkinsonism: antichol.
Akathsia: reduce antipsych. OR propranolol OR low dose clonazepam
Tardive dyskinesia: tetrabenzene (made WORSE by procyclidine)
SSRI Choice
Citalopram and fluoxetine currently preferred
Sertraline useful post MI
Fluox in children
SSRI SE
GI upset GI bleed (If using NSAID give PPI) Inc. anxiety and agitation shortly after starting Fluox and parox higher propensity for drug interactions
QT interval and antideps?
(Es)citalopram a/w dose dependent QTc prolongation and should not be used in those w/preexisiting long QT or in combo w/other QT lengthening
Max citalopram dose: 40mg/d 20 for >65 or hepatic impairment
Interactions of antidepressants
NSAID and aspirin: give PPI
Warfarin/heparin: avoid SSRI consdier mirtazipine
Triptans: avoid SSRI
MAOI: risk serotonin syndrome when given w/SSRI
SSRI in pregnancy
weight up benefits vs risk
1st trim: inc. risk congenital heart defect
3rd: inc. risk persistent pulmonary htn of newborn
Parox has inc. risk congenital malformations (first trim in particular)
Safest: sertraline, citalopram, fluoxetine
Antipsych in elderly pts risk
Increased risk stroke and VTE
non EPSE of antipsych
antimusc: blurred vision, retention, constipation,
sedation and weightgain
Hyperprolactin
Neuroleptic malignant syndrome:pyrexia and stiffness
Red. seizure threshold
Prolonged QT
TCA SE
Drowsiness Dry mouth Blurred vision Constipation + retention QT prolongation
Choosing TCA
Low dose amitriptyline fofr neuropathic pain and headache prophylaxis (tension/migraine)
Lofepramine: lower tox. in OD (safer)
Amitriptyline + doselepin are most dangerous in OD
More sedative: amitriptyline, clomipramine, dosulepin, trazadone
Less sedative: impramine, lofepramine, nortriptyline
Switching Antidep.
- From (es)citalopram, sertraline, paroxetine to another SSRI: withdraw before starting new
- From fluox. to another SSRI: w/d then leave 4-7d gap (long t1/2), low dose new SSRI
- From SSRI to TCA: cross taper (except fluox - withdraw before new)
- From (es)citalopram, sert., parox. to venlaflaxine: cross taper cautiously (start 37.5OD and inc v slowly)
- From fluox. to venla. (w/d and start ven. at 37.5 OD and inc v slowly)
TAKE HOME: Fluox has long t1/2 to long switch
Clozapine SE
agranulocyosis, neutropenia Red. seizure threshold Constip. Myocarditis (baseline ECG before starting Rx) Hypersalivation
Li SE and monitoring
N+V + diarrhoea Fine tremor Nephrotox.(polyuria 2ndry to nephrohgenic DI) Thyroid enlargement (and hypothyroid) ECG: T wave flattening/inversion Wt gain Idiopathic intracranial htn
Li monitoring
Li levels wkly after starting and after each dose change until levels are stable
Once estab. Li levels checked 3monthly
Thyroid and renal 6mly
Pts given info booklet, alert card, record book
Benzodiazepines pharm
Enhances GABA (inc. freq. of opening)
Barbs inc. duration
Sedative, hypnotic, anxiolytic, antconvulsant, muscle relax
Should not use >4wk
Bz w/d
Insomnia Irritability Anxiety Tremor Loss of appetite Tinnitus Perspiration Perceptual disturbance Seizure
