Drugs - Antipsychotic - Typical 01

Question 1

Which are the typical antipsychotic agents?

Answer 1

Phenothiazine/Thoxanthene:

• Aliphatic Substitution: Chlorpromazine (CPZ)
• Piperidine Ring: Thioridazine (Mellaril)
• Piperazine Ring: Fluphenazine (Prolixin)

Butyrophenones:

• Haloperidol (Haldol)
• Droperidol

Dipenzoxazepines:
- Loxapine (Loxitane)

Dihydroindolone:
- Molindone (Moban)

Question 2

Which of the Phenothiazines have weak potency and which have high potency?

Answer 2

Weak:

• Aliphatic (Chlorpromazine)
• Piperidine (Thioridazine)

Strong
- Piperazine (Fluphenazine)

Question 3

What is the method of action of chlorpromazine and thioridazine?

Answer 3

Block alpha-1 and H1 so you get orthostasis and sedation

Question 4

Describe the EPS effects of the Phenothiazines

Answer 4

High EPS - Fluphenazine
Moderate EPS - Chlorpromazine
Least EPS - Thioridazine (also least TD)

Question 5

What are the side effects of chlorpromazine?

Answer 5

Contact dermatitis, photosensitivity, skin and ocular pigmentation (reversible deposits in cornea and lens)

Question 6

What are the side effects of thioridazine?

Answer 6

Prolongs the QT interval, decreased libido, retrograde ejaculation, skin and ocular pigmentation (irreversible deposits in the retina so limit to 800 mg per day or blindness may result)

Question 7

Describe the anticholinergic effects of the phenothiazines

Answer 7

High - Thioridazine (so least EPS)
Medium - Chlorpromazine (so moderate EPS)
Least - Fluphenazine (so high EPS)

Question 8

What is true about the EPS risk for all antipsychotic agents?

Answer 8

It is usually directly proportional to potency, unless the agent has anticholinergic activity or 5HT2A receptor antagonist

Question 9

Which phenothiazines has the best anti-emetic activity?

Answer 9

Fluphenazine (prochlorperazine = Compazine) blocks CTZ

Question 10

Which phenothiazines is available in intramuscular depot forms?

Answer 10

Fluphenazine

Question 11

Which antipsychotics are available in intramuscular depot forms?

Answer 11

• Fluphenazine (enthalate and decanoate ester prodrugs)
• Haloperidol (decanoate)
• Risperidone (microspheres)
• Paliperidone palmitate

Question 12

Besides fluphenazine, which other piperazine agents are also very potent antipsychotics?

Answer 12

• thiothixene
• perphenazine
• trifluoperazine

Question 13

Does fluphenazine have sedative effects?

Answer 13

No, insignificant

Question 14

Which phenothiazine has the least orthostasis?

Answer 14

Fluphenazine