Antipsychotics Flashcards
Schizophrenia (43 cards)
What are the drug classes for Schizophrenia and their MOA?
Dopamine Receptor Antagonist
1. Typical Antipsychotic (D2)
2. Atypical Antipsychotic (D2, 5HT2A)
3. Benzodiazepines (GABA)
What are the goals of therapy for Schizophrenia?
Acute Stabilization
1. Reduce harm to self or others
2. Reduce symptoms
Stabilization and Maintenance
1. Relapse prevention
2. Adherence
3. QOL
What is the role of antipsychotics?
Calm down disturbed patients (Short-term tranquilizing effect without losing consciousness)
What are the 4 dopaminergic pathways in the brain?
- Mesolimbic (Reward): Positive Sx
- Mesocortical (Cognition): Negative Sx
- Nigrostriatal (Motor): EPSE
- Tuberoinfundibular (Milk): Prolactin
What are the postulated effects related to the neurotransmitters?
- D2: Positive Sx, EPSE, Prolactin
- 5HT2A: Negative Sx
- H1: Sedation, weight gain
- Alpha: Lightheadedness
- M1: Dry mouth, constipation, urinary retention
- IKr: QTc prolongation
What are the postulated effects related to different serotonin types?
5HT1A: Anxiety reduction
5HT2A: Depression reduction
5HT2C: Weight gain, appetite
5HT3: Nausea, vomiting
What is the criteria for adequate trial of antipsychotic in schizophrenia?
Optimal dose + 2 to 6 weeks duration
What is the criteria for treatment resistant schizophrenia?
Failed 2 or more adequate trials of antipsychotics (including at least one SGA)
What are the treatment options and dosing for acute agitation (psychiatric emergency) if the patient is compliant to medicine?
Either of these options:
(A) Oral Lorazepam 1 – 2mg
(B) Oral Antipsychotic:
- Haloperidol 2 – 5mg tablet/solution with pre-treatment ECG
- Risperidone 1–2mg tablet/ODT/solution
- Quetiapine 50-100mg Tablet/IR
- Olanzapine 5 – 10mg Tablet/ODT
What are the treatment options and dosing for acute agitation (psychiatric emergency) if the patient is NOT compliant to medicine?
Either of these options:
(a) IM Lorazepam 1 – 2mg
(b) IM Olanzapine 5-10mg; 2nd dose ≥2h after 1st dose; 3rd dose ≥4 h after 2nd dose.
(c) IM Aripiprazole 9.75mg
(d) IM Haloperidol 2.5 – 10mg, with pre-treatment ECG
(e) IM Promethazine 25-50mg
(f) (a) + (d)
(g) (d) + (e)
Why is it that IM Olanzapine and IM Lorazepam must not be given within 1h of each other?
Risk of cardiorespiratory fatality
Compare IM Aripiprazole with IM Olanzapine. Why will I choose one over another?
IM Aripiprazole less hypotensive than IM Olanzapine option
What can be used for catatonia during psychiatric emergency?
PO/IM Lorazepam 1-2 mg
Which antipsychotics can be consolidated as once-daily dosing and why?
Chlorpromazine, Sulpiride; Amisulpride, Clozapine, Quetiapine
Long half-life. Need to consider the risk of hypotension and seizures when consolidating doses!
What is the course of treatment response to antipsychotics?
Early Improvement
Week 1: Agitation, aggression and hostility reduced
Week 2-4: Paranoia, hallucinations reduced, thought organization
Late Improvement
Week 6-12: Delusions reduced, negative symptoms improve
Month 3-6: Cognitive symptoms improve (with SGA)
List the four types of EPSE and in layman terms
Dystonia: Muscle spasm and stiffness in the face, neck, back
Pseudo-parkinsonism: Uncontrollable shaking of limbs
Akathisia: Restlessness and need to keep moving constantly
Tardive dyskinesia: Smacking lips, moving of jaws and tongue
List the treatment and prophylaxis options for Dystonia EPSE
Benztropine 1-2 mg (Max: 6 mg/day)
- Initial: IM (once)
- Subsequent: PO BD to TDS
OR
Diphenhydramine 25-50 mg (Max: 300 mg/day)
- Initial: IM (once)
- Subsequent: PO q4-12h
List the treatment and prophylaxis options for Pseudo-parkinsonism EPSE
Trihexyphenidyl 1 mg/day (Range PO 5-15 mg/day)
List the treatment and prophylaxis options for Akathisia EPSE
PO Clonazepam 0.5 mg/day; increase daily dose based on response and tolerability by 0.5 mg every 5 days up to 4 mg/day in 2 divided doses
PO Propranolol 10 mg BD (Max: 120 mg/day)
List the treatment and prophylaxis options for Tardive Dyskinesia EPSE
None. Discontinue any anticholinergics, reduce the dose of antipsychotics
List of Typical Antipsychotics (D2 Neuroleptics) in NUH
- Haloperidol (0.5 mg green, 1.5 mg white, 5 mg pink)
- Chlorpromazine HCL (Largo, White tablet)
- Trifluoperazine (Stilizan, Blue tablet)
- Sulpiride (Devodil, White tablet)
Haloperidol: Formulations available, usual dose range for schizophrenia and max dosing?
Formulations
- 1.5 mg, 5 mg Tablet
- 2 mg/mL Oral Solution
- 5 mg/mL Injection
Max dosing varies per indication.
Usual Dose Range:
PO 3-5 mg BD (5-15 mg/day)
IM 2-10 mg per dose
Absolute max dosing: 100 mg/day, but doses >30 mg/day are in general not recommended
Chlorpromazine: Formulations available, usual dose range for schizophrenia and max dosing?
Formulations:
- 25 mg, 100 mg Tablet
- 50 mg IJ* EX
Max dosing varies per indication.
Usual Dose Range:
PO 25 mg BD (50-400 mg/day)
Absolute Max dosing: 800 mg/day
Trifluoperazine HCL: Formulations available, usual dose range for schizophrenia and max dosing?
Formulation: 5 mg Tablet
Usual Dose Range: 2-20 mg
Max dosing: 40 mg/day
