Schizophrenia

Question 1

What are the symptoms of schizophrenia?

Answer 1

At least 2 out of 5 of the following:
1. Hallucination
2. Delusion
3. Disorganized Speech
4. Grossly disorganized or catatonic behavior
5. Negative symptoms
(Affective flattening, Avolition)

Social and Occupational dysfunction

Exclude schizoaffective disorders and substance abuse

Continuous signs for 6 months

Question 2

How to overcome poor treatment adherence in schizophrenia?

Answer 2

IM Long acting injections
Community Psychiatric Nurse
Caregiver education

Question 3

In which conditions should we take precaution for antipsychotic use?

Answer 3

1. CVD (QTc, ECG)
2. PD (EPSE)
3. BPH
4. Glaucoma (Narrow-angle)
5. Severe respiratory disease
6. Blood dyscrasia
7. Dementia in elderly (Stroke/mortality risk)

Question 4

Comment on the PK of PO Antipsychotics

Answer 4

Tmax 1-3 hours, Rapid absorption (Except Brexpiprazole, Olanzapine, Aripiprazole)

Long half-life and may be consolidated as once-daily dosing
(Except Chlorpromazine, Sulpiride, Amisulpride, Clozapine, Quetiapine)

Take with food for lurasidone and ziprasidone

Question 5

PO Antipsychotic maintenance dosing
1. Clozapine
2. Olanzapine
3. Quetiapine
4. Risperidone
5. Haloperidol

Answer 5

1. Clozapine
   - 12.5 mg ON/BD Day 1
   - 25-50 mg ON Day 2
   - Usual range 200-450 mg/day
2. Olanzapine 10 mg/day
3. Quetiapine 25 mg BD (150-500 mg/day)
4. Risperidone 2 mg/day divided dose
5. Haloperidol 5-15 mg/day (TDS dosing)

Question 6

Dystonia
1. Description
2. Risks
3. Management

Answer 6

1. Spasm within min to hours
2. High-potency antipsychotics (Haloperidol)
3. IM Anticholinergics (Benztropine, Diphenhydramine)

Question 7

Pseudo-parkinsonism
1. Description
2. Risks
3. Management

Answer 7

1. Tremors, rigidity within days to weeks
2. Elderly females, previous trauma
3. Reduce antipsychotic dose / Switch to SGA; PRN Anticholinergics (Benzhexol, benztropine)

Question 8

Akathisia
1. Description
2. Risks
3. Management

Answer 8

1. Restlessness while sitting within hours to weeks
2. High potency antipsychotics > Risp > Olan > Quet/Cloz
3. Reduce antipsychotic dose or switch to SGA; Give clonazepam low dose PRN and propranolol 20 mg TDS. Anticholinergics are NOT helpful

Question 9

Tardive dyskinesia
1. Description
2. Risks
3. Management

Answer 9

1. Orofacial movements, hand pelvic thrusting
2. FGA > SGA and worsens with anticholinergic
3. Discontinue anticholinergic, reduce antipsychotic dose or switch to SGA. Valbenazine 40-80 mg/day or clonazepam PRN can be considered

Question 10

Hyperprolactinemia
1. Description
2. Risks
3. Management

Answer 10

1. Gynaecomastia in males; Galactorrhea / Amenorrhea / Loss of Libido in females
2. High risk = Olanzapine, clozapine; Low risk: Aripiprazole, Lurasidone
3. Switch to aripiprazole

Question 11

What are some CV side effects of antipsychotics?

Answer 11

1. Orthostasis
2. QTc prolongation
3. VTE/PE (Low potency FGA)

Question 12

Neuroleptic malignant syndrome
1. Description
2. Risks
3. Management

Answer 12

1. Muscle rigidity, FEVER, autonomic dysfunction (PR, BP, sweating), altered consciousness, CK rise
2. High potency antipsychotics
3. IV Dantrolene 50 mg TDS (PO Dopamine agonist), later switch to SGA

Question 13

Agranulocytosis
1. Description
2. Risks
3. Management

Answer 13

1. WBC drop, absolute neutrophil count drop
2. Clozapine
3. Discontinue if severe (WBC < 3 X 10^9) or ANC < 1.5 X 10^9)

Question 14

Monitoring parameters for antipsychotics

Answer 14

General: BMI, FBG, Lipid panel, BP, EPSE exam q 3 months

Drug Specific: WBC, ANC, ECG

Question 15

Drug Interactions with antipsychotics

Answer 15

CNS depressants (Added CNS effect)
Anticholinergics/Antihistamine (Added ADR)
Antihypertensives (Orthostasis)
CYP1A2 Inhibitors (Fluvoxamine, Quinolones, Macrolides) affect Clozapine importantly
Carbamazepine (Agranulocytosis)