Psych drugs

imo132's version from 2017-09-20 09:13


Question Answer
East Asians & APsMore susceptible to EP & ACh SE, lower risk of tardive dyskinesia
Lithium SEHypothyroid, polyuria & polydipsia, fine tremor, muscular weakness, EPSE, memory difficulty, metallic taste, N&V
Lithium therapeutic range0.5-1.2, check after 5 days of initiating/changing, 8 hours after last dose, EUC every 3-6 mo, TFT 6-12 mo, calcium yearly
Lithium toxicity>1.5 mmol/l, with dehydration from poor fluid intake, diarrhea/vomiting, diuretics, NSAIDs
Lithium toxicity SxAtaxia, vomiting, coarse tremor, hemiplegia, disorientation, dysarthria, myoclonus, impaired consciousness, hypertonia, seizures, long QT, AKI, death, Rx HCO3
ParoxetineHighest rate of discontinuation symptoms (with venlafaxine), with weight gain, sexual dysfunction
Short half-life ADParoxetine, fluvoxamine, venlafaxine, high rates of discontinuation symptoms
Long half-life ADFluoxetine, low risk of discontinuation symptoms
ClozapineAtypical, fewer EPSE, lowest mortality & suicide rate, SE weight gain, VTE, seizures
CocaineBlocks DA, NA, 5HT, SE long QT, dissection, colitis, sympathetic, Rx benzos
MDMARx dantrolene for hyperthermia
HaloperidolTypical AP, most commonly discontinued AP, weight neutral
Atypical AP5HT2A & D2 antag, partial 5HT1A & D2 ag, less EPSE & hyperprolactinaemia
SSRI SELow libido & orgasm, fuzzy head, jitteriness at beginning, withdrawal, nausea, diarrhoea, dizziness, headache, insomnia, suicidal ideation
SNRIsUsed in melancholic depression, withdrawal syndrome common, venlafaxine cardiotoxic, duloxetine
DuloxetineSNRI, SE nausea, somnolence, dizziness, dry mouth
FluoxetineSE rash, strange dreams, suicidal ideation
MirtazapineTCA, 5HT, H2, SE weight gain, sedation, oedema, seizures, agranulocytosis
TCAsMost effective in depression but ACh & histamine SE, nocte as sedating, poor tolerability, can use in drug/alcohol use, overdose Rx HCO3
TCA SEDry mouth, cavities, drowsiness, weight gain, hypoTN, cardiotoxicity, long QT (ECG), sedation, sexual dysfunction
ECTFor melanchotic/psychotic depression, inability to eat, suicidal or tormented, bipolar, mania, need 6-18 treatments, 2-3x per week
ECT SESpotty retrograde memory loss, post-ictal headache & confusion, BP instability, bradycardia
DystoniasIn 10%, young males, neuroleptic-naive, high potency drugs eg haloperidol, substance abuse, onset minutes if IM/IV, Rx ECT, Botox
Pseudo-parkinsonismIn 20%, elderly females, head injury, stroke, with salivation, onset days-weeks, Rx reduce dose, atypical, anticholinergic during day
AkathisiaIn 25%, with substance abuse, onset hours-weeks, from D2 blockade via 5HT2A stimulation
Tardive dyskinesiaIn 5%, elderly women, previous acute, substance abuse, haloperidol, onset months-years, Rx reduce, atypical, benzos, propranolol, Vit E
Hyperprolactinaemia APAmisulpride, typicals, risperidone
No hyperprolactinemiaChlorpromazine, aripiprazole, quetiapine, clozapine, olanzapine
Hyperprolactinaemia DxSerum 1 hr post waking/eating, women <25 ng/ml (530 mIU/L), men <20 (424 mIU/L), refer if >2500 mIU
Long QT>500 arrhythmia, >650 torsades or sudden death, APs interact with K (repolarisation), TCAs with Na (depolarisation), annual ECG
Long QT Rx>470 reduce dose or switch drug, >500 or abnormal T switch drug & refer to cardiologist
Weight gainFrom 5HT2C antag, H1 antag, hyperprolactinaemia, increased leptin, from clozapine & olanzapine
BleedingFrom SSRIs via blockage of 5HT uptake into platelets, increased with NSAIDs, anticoags & antiplatelets, liver cirrhosis, Rx add PPI
HyponatremiaFrom AD via increased ADH via high 5HT & NA, in elderly with thiazide/ACE-I, more with SNRI, less with TCA, none with Mirtaz
CYPFewer poor CYP2D6 metabolisers in Asian & African pop than caucasian but lower CYP2D6 activity in east Asians, affects citalopram dosing
Discontinuation syndDizziness, unsteadiness, weakness, N/V, headache, anxiety, insomnia, URT Sx, paraesthesias, from paroxetine, fluvoxamine, venlafaxine (short half life), 1 week
Mania drugsLithium, olanzapine, aripiprazole, risperidone
D1-REncourages use via DA release, becomes overexpressed after repeated exposure
D2-RInhibits use via inhibition of DA release
AP initiationPatient feels better after first 3 months, will relapse after 6 months if ceased
AD onset6 weeks for anxiety, 2 weeks for depression
EPSERisperidone > chlorpromazine, Rx with anticholinergics
Chlorpromazine SEPhotosensitivity
QuetiapineAtypical, SE constipation, weight gain, hyperglycemia, NMS
No EPSEClozapine, olanzapine, sertindole, quetiapine
Most effective APClozapine > amisulpride, olanzapine, risperidone
SertralineSSRI, activating (makes patients anxious) so take in morning, diarrhoea
CitalopramSSRI, long QT with high dose (none with escitalopram)
Teratogenic ADSSRI, lithium contra in breastfeeding, all mood stabilisers (use AP eg quetiapine)
Schizophrenia deathMore cardiac than suicide (twice risk CHD), often sudden cardiac death from long QT, premature death by >15 years
NMS20% mortality, incidence 3%, typical APs, common in first 2 weeks of therapy, sudden DA reduction
NMS RFInitiation of therapy, high doses, rapid escalation, switching class, IV/IM, agitation, catatonia, dehydration, lithium, depots
NMS tetradMuscle rigidity, mental state change, hyperthermia, autonomic instability
Acute dystoniasFrom IV/IM AP via DA blockade, laryngeal spasm lethal, Rx benztropine (anticholinergic)