Drugs used in Psychiatric Disease Flashcards
What are the core and secondary symptoms of depression and how to they relate to making a diagnosis?
Core symptoms: (need 2 of 3 of these)
Low mood
Anhedonia
Decreased energy
Secondary symptoms:
Sleep disturbance, Hopelesness, Reduced concentration, Irritibility, Self-harm/suicidal thoughts
Explain what is meant by the “monoamine hypothesis” of depression
What are the other 2 theories for the pathophysiology of depression?
Depression thought to be due to deficiency of monoamine neurotransmitters (NA and serotonin)
Neurotransmitter Receptor Hypothesis
The Monoamine Hypothesis of Gene Expression
What are the 4 types of antidepressant that can be used clinically?
Tricyclic antibiotics (TCAs)
Serotonin and Noradrenaline reuptake inhibitors (SNRIs)
Noradrenaline reuptake inhibitors (NARIs)
Selective Serotonin reuptake inhibitors (SSRIs)
Give some examples of SSRIs
Sertraline
Fluoxetine
Citalopram
How are SSRIs absorbed?
Where are they metabolised?
In the gut
Metabolised in the liver
List some common and some rare side effects of SSRIs
Common: anorexia, nausea, diarrhoea
Rare: precipitation of mania, increased sucicidal intention
How to TCAs work?
Inhibit the reuptake of NA at the nerve terminals
Give some examples of TCAs
Amitriptyline
Clomipramine
How are TCAs absorbed?
Where are they metabolised?
The gut
Metabolised in the liver
List some of the side effects of TCAs
CNS: sedation, lowering of seizure threshold
CVS: tachycardia, postural hypotension
GI: constipation
What would be some of the consequences of a TCA overdose?
Hypotension
Seizure
Arrhythmias
Tachycardia
Give some named examples of SNRIs
Duloxetine
Venlafaxine
What is the definition of psychosis?
Lack of contact with reality
What are the symtoms of paranoid schizophrenia?
Disturbances in thinking
Hallucinations
Delusions
Unusual speech
Lack of insight
What is the definition of a “hallucination”?
A perception in the absence of an external stimulus
(auditory, olfactory, visual, gustatory, tactile)
What is the definition of a “delusion”
A fixed false belief that is out of keeping with someones culute or religious belief
Briefly explain the dopamine theory of schizophrenia
Theory of disturbed and hyperactive dopaminergic signal transduction leading to schizophrenia
What is the evidence that supports the dopamine hypothesis of schizophrenia?
Amphetamine (increases dopamine) causes very similar symptoms to + schizophrenia symptoms
Parkinson’s disease treatment that do the same can induce schizophrenia like symptoms
Dopamine antagonists are used in the treatment of schizophrenia
What are the main dopamine pathways and what are they each responsible for?
Mesolimbic: emotional response and behaviour
Meso-cortical: important in arousal and mood
Nigrostriatal: key pathway damaged in PD
Tuberoinfundibular: in hypothalamus and pituitary gland
Name some first generation or “typical” antipsychotics
Haloperidol
Chloropromazine
Name some atypical antipsychotics
Olanzapine
Risperidone
Quetiapine
Clozapine
What is the definition of bipolar disorder?
A mental illness that is assoicated with periodic episodes of depression and hypomania/mania
What kind of things might you notice in a patient with mania?
Unusal excitement, happiness or optimism
Overactivity
Poor concentration and short attention span
Poor sleep
Rapid, disordered, caotic speech
Poor judgement
Increased interest in sex
Psychotic symptoms
Give some examples of mood stabilisers that might be used in the treatment of bipolar disorder
Lithium - most effective
Sodium valporate - antiepileptic
Carbamazepine- antiepileptic
Lamotrigine - antiepileptic
How does Lithium work?
May compete with magnesium and calcium ions
Increases 5HT and possibily their receptor sites in long term use
Attenuates the effect of neurotransmitters
Where is Lithium excreted?
What needs to be checked before starting Lithium and every 6 months after?
Via the kidneys
Renal function
List some of the side effects of Lithium
Memory problems
Thirst
Polyuria
Tremor
Weight gain
Drowsiness
Hair loss
Rashes
What are the toxic effects of Litihum and how can they be treated?
Vomiting, diarrhoea, coarse tremor, cognitive impairment
Treat supportively, anticonvulsants, increase fluid intake, haemodialysis
What are the two types of drug used to slow the progression of dementia, give examples of each
Acetyl Cholinesterase Inhibitors:
- Donepezil
- Galantamine
- Rivastigmine
NMDA antagonist:
-Memantine
What is the mechanism of action of Acetyl-cholinesterase inhibitors?
Prevents the production of acetyl-cholinesterase which would normally break down acetylcholine
Acetylcholine plays a role in arousal, memory, attention and mood
According to NICE Acetyl Cholinesterase inhibitors can be used to treat what?
Mild- moderate dementia
According to NICE Memantine can be used to treat what?
Moderate- severe dementia
What are the actions of all antipsychotics overtime?
Hours: sedation
Hours: tranquilisation
Days-weeks: antipsychotic
Weeks: activation of negative symptoms
Hours/days: extrapyramidal side effects
Why might an atypical antipsychotic be more acceptibe to patients that a “typical” antipsychotic such as Haloperidol?
Less extrapyramidal side effects
Can be taken once daily
Can get as dissolvable preparations
List some extrapyramidal side effects (EPSEs)?
Parkinsonism
Acute dystonia
Akathisia
Tardive dyskinesia
List some of the things you might see in typical antipsychotic toxicity
CNS depression
Cardiac toxicity
Risk of sudden death
List some of the behavioural, psychological and physical symptoms of anxiety
Behavioural: avoidance
Psychological: fear of dying, going crazy
Physical symptoms: light headedness, hot/cold flushes, SOB, numbness, nausea
What is the first line treatment for anxiety?
Non-pharmacological approaches e.g. CBT
Give some examples of benzodiazepines
Diazepam
Lorazepam
How do benzodiazepines work?
Full agonist of GABA receptor site which leads to enhancement of GABA effects
This has inhibitory effects on the brain
What property of benzodiazepines means that they diffuse into the CNS rapidly?
They are highly lipid soluble
When prescribing benzodiazepines, you should be aware that they can cause the need for an increased dose to have the same effect, known as _________. Discontinuation of treatment can cause withdrawl, known as ___________.
Tolerance
Dependence
List some common, occassional and rare side effects of Benzodiazapines
Common: Drowsiness, dizziness, psychomotor impairment
Occassional: dry mouth, blurred vision, GI upset, ataxia, headache
Rare: amnesia, restlessness, rash
Why should benzodiazapines not be used in pregnancy?
They can cause cleft lip and palate
Late in pregnancy: respiratory depression, feeding difficulties in baby
Which drug might be useful in reversing the effects of benzodiazapine overdose?
Flumazenil
