Antipsychotics

Question 0

What is the major neurotransmitter that is associated with a

Schizophrenia?

Answer 0

Dopamine - too much gives positive symptoms and too little gives negative

Question 1

Schizophrenia is involved with malfunctioning in two pathways, the mesolimbic and mesocortical. Which is involved with positive symptoms and which is involved with negative?

Answer 1

Over activity of mesolimbic causes positive

Under activity of mesocortical causes negative

Question 2

Name two drugs that can produce a psychosis that closely mimics schizophrenia

Answer 2

Amphetamine and cocaine

Question 3

Antipsychotic drugs work by blocking what receptor?

Answer 3

D2

Question 4

Blocking of dopamine in the nigrostriatal pathway leads to what side effets of antipsychotics?

Answer 4

Parkinsonism - extra pyramidal reactions

It’s a motor pathway linking substantia nigra to the basal ganglia

Question 5

Explain how blocking D2 receptors can worsen negative symptoms of schizophrenia

Answer 5

Neurons with D2 receptors are inhibitory to GABAergic neurons (they inhibit the inhibitor so net excitatory function). Block D2 and you get increased activity of GABAergic neurons (increased inhibitory effects) -> negative symptoms

Question 6

Blocking dopamine, like in treatment for schizophrenia, can have what endocrine adverse effect?

Answer 6

Galactorrhea because dopamine usually inhibits prolactin

Question 7

Name the four classical antipsychotic drugs

Answer 7

Chlorpromazine
Fluophenazine
Haloperidol
Thioridazine

Question 8

The classical antipsychotics are subclassified based on potency with the higher potency drugs being MORE liekly to cause extra pyramidal effects. Name the two more potent ones

Answer 8

Fluphenazine

Haloperidol

Question 9

The classical antipsychotics are subclassified based on potency with the higher potency drugs being MORE liekly to cause extra pyramidal effects. Name the two with lower potency

Answer 9

Chlorpromazine
Thioridazine

ie LESS likely to cause extra pyramidal reactions

Question 10

Which subtype of antipsychotic is more effective at treating negative symptoms? Classic or atypical?

Answer 10

Atypical

Question 11

What makes the atypical antipsychotics atypical?

Answer 11

They have higher affinities for receptors other than D2

Question 12

Which subtype of antipsychotic is more liekly to cause tardive dyskinesia? Classical or atypical?

Answer 12

Classical

Question 13

Which two atypical antipsychotics are LEAST likely to cause extra pyramidal reactions?

Answer 13

Clozapine and quetiapine

Question 14

Which atypical antipsychotic is a partial agonist at D2?

Answer 14

Aripiprazole

Question 15

What is the typical onset of action for antipsychotic drugs?

Answer 15

Less than 24 hours

Question 16

Antipsychotics generally have an additional systemic effect outside of treatment for schizophrenia. What is it? Two exceptions

Answer 16

Antiemetics

Aripiprazole and thioridazine

Question 17

If a patient is taking antipsychotics, what drug interactions do you have to worry about?

Answer 17

None they don’t interfere with the metabolism of other drugs

Question 18

What drug should you NEVER give a patient suffering extra pyramidal effects from antipsychotics?

Answer 18

Levodopa (dopamine)

Question 19

What is the treatment for extrapyramidal effects caused by antipsychotics?

Answer 19

Benztropine
Trihexyphenidyl
Diphenhydramine
Amantadine

Question 20

Akathisia is a common adverse effect of antipsychotics. What is it and what drugs do you use to treat it?

Answer 20

Feeling of inner restlessness

Treat with propranolol (beta blocker) or clonazepam (benzo)

Question 21

Patient taking haloperidol presents with rigidity, tremor, hyperthermia, altered mental status, inc WBC count, increased CK. diagnosis? How do you treat?

Answer 21

Neuroleptic malignant syndrome - AE of antipsychotics (rare but life-threatening)

Give dantrolene or bromocriotine (dopamine agonist)

Question 22

What is the most significant and potentially irreversible adverse effect of antipsychotics? What is it? How do you treat it? (4)

Answer 22

Tardive Dyskinesia

Stop or reduce dose of antipsychotic
Eliminate all drugs with central anticholinergic effects (esp antiparkinsonian drugs and TCAs)
Give diazepam
Clozapine for patients with TD that require antipsychotics

Question 23

Patient taking antipsychotics presents with seizures. Which two drugs are most likely to be causing these symptoms?

Answer 23

Clozapine (atypical) and chlorpromazine (classical)

Question 24

If you prescribe a patient clozapine, what follow up testing is mandatory? Why?

Answer 24

Regular CBC

Causes agranulocytosis in 1-2% of patients

Question 25

Female Patient taking antipsychotis presents with complaints of amenorrhea but infertility. Explain

Answer 25

Blockade of dopamine from her antipsychotics removed the inhibition dopamine had on prolactin. Increased prolactin levels are probably causing her symptoms.

Atypicals are LESS likely to elevate prolactin

Question 26

You prescribe an atypical antipsychotic. What effects might you warn the patient about concerning her weight? How does this compare to classicals?

Answer 26

Atypicals are more likely to cause weight gain (as opposed to classicals) and this can lead to diabetes, HTN, and hyperlipidemia

Question 27

Patient taking an antipsychotic showed QT elongation. Which two drugs could be responsible? Which is more likely to cause ventricular arrhythmias and sudden death?

Answer 27

Ziprasidone

Thioridazine - more likely to lead to sudden death

Question 28

Some antipsychotics can cause deposits in the cornea/lens and some in the retina. Name one drug that causes each

Answer 28

Cornea: chlorpromazine
Retina: thioridazine

Question 29

Other than schizophrenia, name four other diseases antipsychotics can be used to treat

Answer 29

Bipolar (atypical)
Tourette’s
Huntingtons
Alzheimer’s

Question 30

What is the antipsychotic drug of choice? Which drug is only used in refractory patients? Why?

Answer 30

Atypcials are DoC - Risperidone is most popular

Clozapine only used in refractory due to its ability to cause agranulocytosis

Question 31

What is the only antipsychotic that is category B instead of category C?

Answer 31

Clozapine