Antipsychotics and Mood Stabilizers Flashcards
What causes positive symptoms of schizophrenia?
Over-reatcivity of mesolimbic pathway
What causes negative and cognitive symptoms of schizophrenia?
Mesocortical pathway dysfunction
Describe how dopamine may lead to delusions
- Dopamine mediates attention and reward
- Excess dopamine causes inability to jettison irrelevant information
- Brain connects dots of non salient information
- Delusions occur
Describe schizophrenia
- Chronic
- Onset typically early 20s
- Prevalence in 1% of population
Describe 2 cognitive impairments of schizophrenia
- Pattern of impairments
2. Drop in IQ
Describe a negative symptom of schizophrenia
Emotional blunting (social withdrawal, apathy)
Describe a positive symptom of schizophrenia
Psychosis (delusions, hallucinations, impaired insight)
Name 5 typical antipsychotic drugs
- Chlorpromazine
- Fluphenazine
- Flupentixol
- Haloperidol
- Sulpiride
Name 6 atypical antipsychotic drugs
- Olanzapine
- Quetiapine
- Risperidone
- Aripiprazole
- Amisulpride
- Clozapine
Describe the different in side effects between 1st and 2nd generation antipsychotic drugs
- Typical more likely to produce EPSE (extra pyramidal side effects)
- Atypical more likely to produce metabolic side effects
- 2nd generation have broader receptor profile
What mediates antipsychotic drugs clinical effects?
Antagonism at dopamine D2 receptors
What type of symptoms do antipsychotic drugs improve?
Positive symptoms
Name 2 types of adverse effects mediated by dopamine antagonist for antipsychotic drugs
- EPSE (Nigrostriatal Tract)
2. Prolactin Elevation (Tuberoinfundibular System)
Name 4 types of receptors other than dopamine receptors which mediate adverse effects of antipsychotics
- Serotonin
- Histamine
- Muscarinic
- Alpha adrenergic
Name 4 side effects associated with EPSE
- Acute dystonia
- Parkinsonism
- Akathisia
- Tardive Dyskinesia
What is acute dystonia?
Sudden contraction of a muscle grow
How can acute dystonia be resolved?
Use of an anti-cholinergic agent e.g. procyclidine
Name 3 ways parkinsonism as an EPSE side effect could be resolved
- Reducing dose
- Changing antipsychotic
- Use of anticholinergic agent
What is tardive dyskinesia?
Writhing movements in face, tongue, trunk, arms or leg
What is the best treatment for tardive dyskinesia?
Switch treatment to 2nd generation antipsychotic
Name 3 types of second generation antipsychotics which are particularly susceptible for causing metabolic side effects
- Quetiapine
- Olanzapine
- Clozapine
Name 3 metabolic side effects of antipsychotics
- Weight gain
- Dry mouth / constipation
- Postural hypotension
What 3 receptors mediate weight gain as a metabolic side effect of antipsychotics?
- Antagonism of 5HT2C
- Antagonism of 5HT1A
- Antagonism of H1
What is clozapine used for?
Reserved for use in treatment resistant schizophrenia
What is resistant schizophrenia?
Schizophrenia which has not been resolved with 2 trials of antipsychotic for a minimum of 6 weeks each
Name 3 common side effects of clozapine
- Sedation
- Weight gain
- Hypersalivation
What is a side effect of clozapine which can be fatal?
Neutropenia leading to agranulocytosis
Describe the monitoring of patients on clozapine
- Due to potential for agranulocytosis
- Monitored weekly for 18 weeks
- Biweekly for next 18 weeks
- 4 weekly following first stable 36 weeks
Describe the mechanism of action of aripiprazole
A partial agonist at dopamine D2 receptor
Describe how aripiprazole functionally acts
- Acts as antagonist in presence of increased dopamine transmission in mesolimbic area
- Acts as an agonist in mesocortical area
Name 2 side effects of aripirazole
- Akathisia
2. Agitation
Name 3 psychotic disorders other than schizophrenia which would indicate the use of an antipsychotic
- Delusional disorder
- Severe depression with psychotic symptoms
- Mania with psychotic symptoms
Name 2 non-psychotic disorders which would indicate the use of an antipsychotic
- Maintenance in bipolar affective disorder
2. Adjunctive treatment in depression
Name 3 non-psychotic disorders which have evidence for the use of an antipsychotic
- OCD
- PTSD
- ASD
What 3 types of mood may occur in a person suffering from bipolar disorder?
- Mania
- Depression
- Euthymic (normal)
Name 3 core symptoms of a person suffering from depression
- Persistent sadness
- Tiredness
- Loss of interest
Name 3 possible symptoms of a person suffering from depression outside of the 3 core symptoms
- Disturbed sleep
- Low self confidence
- Suicidal thoughts or acts
What is may mania associated with?
Grandiose delusions
What is mania / hypomania?
A pathological mood state lasting 4 or more days
Name 4 characterizations of mania
- Elated mood
- Overactivity
- Increase energy
- Disinhibition
Describe 3 components of neurobiology of bipolar disorder
- Increased dopamine neurotransmission
- Increase glutamate transmission
- Reduced GABA neurotransmission
Name 3 types of treatment in bipolar disorder
- Treatment of bipolar depression
- Treatment of manic episodes
- Prevention of relapse
What drug must be stopped during a manic episode?
Antidepressants
Name 3 types of drugs which can be used to treat a manic episode during bipolar
- Antipsychotic
- Lithium
- Valproate
Name 3 pharmacological treatments for bipolar depression
- Quetiapine / Olanzapine (+/- fluoxetine)
- Lamotrigine
- Lithium (less effective)
What is a non-pharmacological treatments for bipolar depression?
Psychological treatments e.g. CBT
What is a mood stabilizer?
Effective in preventing recurrence of manic and depressive relapses
Name 4 types of mood stabilizers
- Antipsychotics
- Lithium
- Sodium valproate (depakote)
- Lamotrigine
Name 3 modes of action of lithium
- Inhibits dopamine transmission pre synaptically and post synaptically
- Inhibits glutamate transmission post synaptically
- Increase GABA transmission pre synaptically and post synaptically
Describe the pharmacokinetics of lithium
- Absorption complete 6-8 hours
- No protein binding / not metabolized
- Excreted entirely in urine
- Half life is 20 hours
Describe 3 lithium side effects related to the kidneys and thyroid
- Polyuria / Polydipsia
- Nephrotoxicity
- Hypothyroidism
Name 4 side effects not related to the kidneys and thyroid of lithium
- Leukocytosis
- Minor cognitive effects
- Muscle weakness
- Nausea / diarrhoea
- Weight gain
What can occur during severe lithium toxicity?
Seizures leading to coma and death
Name 4 possible causes of lithium toxicity
- Overdose
- Older patients more vulnerable to toxicity
- Factors affecting salt / water balance
- Medications
Name 4 types of medication which may influence lithium levels
- Thiazide diuretics
- ACE inhibitors
- NSAIDs
- COX-2 inhibitors
What is the predicted mechanism of action of sodium valproate?
Enhances GABA transmission
How is sodium valproate metabolized?
Liver by CYP enzymes
What is the main clinical indication of sodium valproate?
Epilepsy
What are 2 uses of sodium valproate when used as a mood stabilizer?
- Maintenance treatment
2. Treat acute mania
What is a major contraindication of sodium valproate?
Women of childbaring age
Name 3 common side effects of sodium valproate
- Nausea / vomiting
- Drowsiness
- Dizziness
Name 3 uncommon side effects of sodium valproate
- Encephalopathy
- Liver failure
- Pancreatitis
What is the mode of action of lamotrigine?
Acts of presynaptic voltage gated sodium channels to reduce glutamate neurotransmission
How is lamotrigine metabolised?
Glucuronic acid conjugation
What drug may reduce levels of lamotrigine?
Oral contraceptive pill
What is the use of lamotrigine in bipolar disorder?
Second line treatment to prevent bipolar depression
Name 2 severe side effects associated with lamotrigine
- Stevens Johnson Syndrome
2. Toxic Epidermal Necrolysis
Name 4 common side effects of lamotrigine
- Loss of balance
- Nausea
- Drowsiness
- Insomnia