Antipsychotic

Question 1

MOA Of antipsychotics: the therapeutic tract

Answer 1

Mesolimbic tract ( blockade of the dopamine receptor in the mesolimbic tract)
Overactive in the mesolimbic region is responsible for +ve symptome of schiz

Question 2

Antipsychotic block Nigrostriatal (NS) tract in the central dopamine system, causing :

Answer 2

EPSE side effects, such as dystonia, tardive dyskinesia, cogwheel, rigidity

Question 3

What are the therapeutic and adverse effects , when antipsychotic blocks D2?

Answer 3

1. Therapeutic: improve +ve symptoms
2. ADE: EPSE, hyperprolactinemia ( sexual dysfunction)

Question 4

When antipsychotic have effect on weight gain, which receptor is blocked?

Answer 4

5HT2c
H1 receptor

Question 5

Antipsychotic blocks IKr receptor, what side effect to monitor?

Answer 5

QTc prolongation

Question 6

When antipsychotic blocks alpha 1 receptor, need to watch out for fall risk due to

Answer 6

Orthostasis hypotension
Sedation

Question 7

2nd Gen antipsychotic, have dual action, due to the effect on :

Answer 7

1. D2 antagonism(improve +ve symptoms)
2. 5HT1a agonism (anxiolytic)

Question 8

Some e.g . Of 2nd Gen antipyschotic:

Answer 8

1. Quetiapine
2. Risperidone(FDA approved to used in BPSD)

Question 9

What to do when patient failed treatment with two different antypsychotics?

Answer 9

Clozapine

Consider clozapine in those who are treatment resistanct (failed two or more trials of different antipsychotics.

Question 10

When pt is on clozapin, what monitoring should be carried out?

Answer 10

Hematological monitoring weekly for 18weeks then monthly: to monitor for leukopenia, agranulocytosis (decreased ANC)
Discotinue Clozapin if severe (TWC <3 or ANC <1.5)
Monitor fasting blood sugar and lipid panel 3/12 after initiating

Question 11

Pt is on 1st Gen antipyschotic treatment, presented in ED for fever, tachycardia, diaphoresis, labile BP, and CK 1000s, what is the dx ? What to do?

Answer 11

Neuroleptic malignant syndrome (NMS)
1. IV dantrolen 50mg TDS
2. Oral dopamine agonist ( e.g. amantadine, bromocriptine)
3. Support measures (ABC)
4. Switch to SGA

Question 12

Pt is on Clozapine, or Olanzapine, noted to have significant increase in wt, HbA1C 7.9%, increased in LDL, what to do?

Answer 12

1. Life style modification (diet and exercises)
2. Treat hyperlilidemia
3. Treat DM
4. CHANGE TO LOWER risk agents

Question 13

Pt is on long term antipsychotic, developed “ orofacial movement, choreiform hand movement, pelvic thrusting”, what can be done to help the pt?

Answer 13

1. Discontinue any anticholinergics
2. Decrease antipsychotic dose or to switch to SGA
3. Reversible inhibitor of vesicular monoamine transporter 2 : Valbenazine 40 - 80 mg/day

Question 14

Pt was given high dose haloperidol, suddenly develiped muscle spasm, with oculogyric crisis(dystonic anf conjugate and upward deviation of eyes), what to do next?

Answer 14

IM anticholinergic (e.g benztropine)

Question 15

In order to increase absorption for Lorazidone or Ziprasidone, how should the med be taken ?

Answer 15

With food

Question 16

List some drugs would increase the risk of agranulocytosis when pt is on clozapine:

Answer 16

1. Carbamazepine
2. FLUVOXAMINE, Quinolones Macrolides, Isoniazid, (CYP1A2 inhibitor, increase Clozepine PDC)

Question 17

When pt is on antipsychotic treatment, what is the time course of treatment response?

Answer 17

1. 1st week: decrease agitation,
2. 2-4weeks, decrease paranoia, hallucination amd bizarre behaviours
3. 6 to 12 weeks, delusion and negative symptoms may improve
4. For pt with SGA, Cognitive treatment may improve after 3 to 6 months

Question 18

Acute agitation management:

Answer 18

1. Deescalate
   2nd line: consider oral antipsychotic +/- benzodiazepine .
   3rd. If refuse oral med, consider fast acting IM alternatives (e.g IM haloperidal 5mg with ECG +IM lorazepam 2mg

Lastly, monitor adverse effects of med: e.g. dystonia, pseudoparkisonian

Question 19

How to manage poor adherance rate to antipsychotic:

Answer 19

1. IM long acting antipsychotics (e.g IM halo Decanoate) (inj with bigger G needle as it is oil based)
2. Refer to community paychiatric nurses
3. Proper education

Question 20

ABC SGA with less QTc prolongation side effect:

Answer 20

A. Aripiprazole
B. Brexpiprazole
C. Cariprazine

Question 21

A male patient on on antipsychotic, experiencing a lot of sexual dysfunction s/e, what can be done to help?

Answer 21

1. Decrease FGA dose
2. Dopamine agonist (e.g. amantadine, bromocriptine)
3. Switch to Aripiprazole (a partial D2 agonist)

Question 22

A PD pt with psychosis and hallucination, what antipsychotic can be given?

Answer 22

1. Clozapine
2. Quetiapine
   (Avoid 1st Gen antipsychotic and olanzapine)