Psychiatry - Drugs Flashcards
Dopamine Hypothesis
Mesolimbic (too much D2) - positive symptoms
Mesocortical (too little D2) - negative symptoms
Tuberofundibular - endocrine/metabolic SE
Nigrostriatal - EPSE
EPSE
Acute dystonia
- Painful spastic contraction
- Give procyclidine
Akathesia
- Restlessness and distress
- Procyclidine/propanolol
Parkinsonism
- Tremor, rigidty and bradykinesia
- Anticholinergics
Tardive dyskinesia
- Involuntary, repeatitive movements
- Tongue, lips face
- Irreversible, anticholinergics make it worse
Neuroleptic Malignant Syndrome
Within 10 days on initiation
- Severe rigidity
- Temp >38 degrees
- Fluctuating consciousness
- Autonomic instability
Depot
1st generation and Risperidone
2-8 weeks, deep IM injection
Increased compliance and bioavailability
Decrease abuse/toxicity
1st Generation - MOA
Decrease D2 in all 4 pathways
1st Generation - Indications
Schizophrenia
Acute mania
Psychosis
1st Generation - Side Effects
Tuberoinfundibular
- Prolactinaemia
- Galactorrhoea, menstual disturbance
Acetylcholine
- Can’t spit can’t see can’t poo can’t pee
Adrenaline/noradrenaline
- Postural hypotension
- Sexual dysfunction
Histamine
- Sedation
- Weight gain
Achetylcholine Side Effects
- Dry mouth
- Blurred vision
- Urinary retention
- Constipation
2nd Generation - MOA
Decreased action on Nigrostriatal = decreased EPSE
Increased on other e.g. adrenergic/histamine = weight gain
2nd Generation - Indications
First line in schizophrenia
Clozapine = Treatment resistant schizophrenia
Clozapine - Indications
Treatment resistant schizophrenia
- 2 or more other antipsychotics tried
- At full dose for 6 months
- With no effect (not stopped due to side effects)
Clozapine - Side Effects
Neutropenia and agranulocytosis
Clozapine - Monitoring
- Weekly FBC etc for 18 weeks
- 2 weekly for first year
- 4 weekly after that
Withdraw if leucocytes <3000 or neutrophils <1500
2nd Generation - Side Effects
Weight gain, dizziness, T2DM, postural hypotension, hyperlipidaemia
Quetipine/Zotepine - Side Effects
QT prolongation
No Ach side effects
2nd Generation - Baseline Monitoring
Bloods
- FBC, UEs, LFTs, HbA1c, Glucose, prolactin, lipids, cholesterol
Physical
- Weight, BP, HR
ECG
- Hx CV/Smoker
- On quetipine or zotepine
Lithium - Indications
BAD prophylaxis
Recurrent/resistant depression
Use for >3 years
- Poor compliance = rebound mania (hard to treat)
Lithium Side Effects - Early
Fatigue Drowsiness Fine Tremor Weight gain Polydipsia Polyuria
Lithium Side Effects - Late
Thryoid problems
Renal failure
CVD
Lithium Toxicity
Mild Drowsiness, ataxia, coarse tremore
Severe:
Convulsions, collapse
Lithium Monitoring - Bloods
Lithium levels checked 12 hours post dose.
3-5 days for the first few weeks until stable, then 3-4 monthly levels
Check kidney and thyroid function too
Lithium - Baseline Monitoring
Weight Renal function TFTs Pregnancy Test ECG
SSRIs - MOA and examples
Inhibit re-uptake of serotonin at the synaptic cleft
- Fluoxetine
- Sertraline
- Paroxetine
- Citalopram
- Escitalopram
- Fluvoxamine
SSRIs - Side effects
Very Common
- GI Disturbance
- Insomnia (do not take at night)
- Sexual disturbance
Common
- Headache
- Decreased appetite
- Restlessness
Rare
- Rash
- Thoughts of self harm
SSRIs - Counselling
How?
- One tablet each day in the morning
Effect
- By week 2, definitely by week 8
Duration
- 12 months to prevent relapse
Stopping
- Wean off
Overdose
- Not toxic
SNRIs - MOA and Examples
Inhibit reuptake of serotonin and noradrenaline
- Venlafaxine
- Duloxetine
SNRIs - Indication
Treatment resistant depression
- increased efficacy and rapid onset
GAD
SNRIs - Side effects
Nausea, headache, sleepiness, dizziness
Cardiotoxic - avoid in heart disease/hypertension
SNRIs - Monitoring
ECG and BP before starting
Tricyclic Antidepressant - MOA and Examples
Inhibit reuptake of noradrenaline and serotonin
- Amitriptyline
- Imipramine
- Lofepramine (not toxic in overdose)
TCAs - Indications
Imipramine - non sedating
Amitriptyline - sedating
Clomipramine - use in OCD
TCAs - Side Effects
Ach side effects
Histamine
Cardiotoxic (avoid in MI/heart block)
Neurotoxic - delirium etc.
TCA - Overdose + Antidote
Very toxic
Increased HR, dilated pupils, low GCS, palpable bladder, seizures, arrythmias
Give Sodium Bicarbonate
NASSA - MOA and Example
Noradrenaline and Serotonin Specific Antidepressant
Mirtazapine
Severe depression, especially if poor sleep/diet
NASSA - Side Effects
Sedation
Weight gain
Dry mouth
Dizziness
SAFE IN OVERDOSE
NARI - MOA and Example
Noradrenaline Re-uptake inhibitor
Reboxetine
Severe depression
NARI - Side Effects
Nausea, anorexia, sweating, dizziness, postural hypotension
SAFE IN OVERDOSE
Risperidone - Side Effects
Low BP
Restlessness
Headache
Sexual dysfunction
Olanzapine - Side Effects
Weight gain
Sedation
Constipation
SSRIs - Side Effects
N+V
Dizziness
Dry mouth
Sexual dysfunction
Increased suicidal thoughts
Mirtazapine - Side Effects
Weight gain
Sedation
Dizziness
Dry Mouth
Venlafaxine - Side Effects
NOT in CVD
N+V
Dizziness
Headache
